Trial Outcomes & Findings for Comparative Efficacy of Self-directed & Therapist-assisted Telehealth Parent Training Intervention for Children With ASD (NCT NCT02721381)

Results Overview

Parents' use of the intervention strategies with their child is measured during a parent-child interaction in the home using the Project ImPACT Intervention Fidelity Checklist (Ingersoll \& Dvortcsak, 2019). Parents are asked to (1) play with their child for 10 minutes with a standard set of toys; and (2) have a small snack or meal with their child for 10 minutes. Parents are instructed to interact with their child as they typically would during both activities. Coders rated the parents' use of each of the five Project ImPACT intervention strategies on a scale of 1 ("does not implement the strategy, or almost all attempts to use the strategy are incorrect.") to 5 ("implements the strategy effectively throughout the session"). Scores for each strategy were averaged to form an overall fidelity rating for each activity. Fidelity ratings for each activity were averaged to form the parent fidelity variable.

Recruitment status

TERMINATED

Study phase

NA

Target enrollment

130 participants

Primary outcome timeframe

Post-treatment (6 months)

Results posted on

2025-02-07

Participant Flow

Recruitment took place in Michigan and focused on underserved communities as defined by residence in a Rural Health and/or Health Provider Shortage Area by the U.S. Health Resource \& Services Administration; however, families did not have to live in an underserved community to be enrolled.

Participant milestones

Participant milestones
Measure	Parent: Self-Directed Group Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Child: Self-Directed Group Child participants will receive Project ImPACT intervention from their parent as trained in the self-directed group.	Parent: Therapist-Assisted Group Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Child: Therapist-Assisted Group Child participants will receive Project ImPACT intervention from their parent as trained in the therapist-assisted group.	Parent: Information and Resource Support Control Group Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.	Child: Information and Resource Support Group Child participants will interact with their parent without training in Project ImPACT.
Overall Study STARTED	24	24	22	22	19	19
Overall Study COMPLETED	21	21	21	21	17	17
Overall Study NOT COMPLETED	3	3	1	1	2	2

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

One family withdrew from IRS control group after random assignment due to displeasure at group assignment and asked for data to be removed.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Child: Self-Directed Group n=24 Participants Child participants will receive Project ImPACT intervention from their parent as trained in the self-directed group.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, parent participant, and child participant and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Child: Therapist-Assisted Group n=22 Participants Child participants will receive Project ImPACT intervention from their parent as trained in the therapist-assisted group.	Parent: Information and Resource Support Control Group n=19 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.	Child: Information and Resource Support n=19 Participants Child participants will interact with their parent without training in Project ImPACT.	Total n=130 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=24 Participants	24 Participants n=24 Participants	0 Participants n=22 Participants	22 Participants n=22 Participants	0 Participants n=19 Participants	19 Participants n=19 Participants	65 Participants n=130 Participants
Age, Categorical Between 18 and 65 years	24 Participants n=24 Participants	0 Participants n=24 Participants	22 Participants n=22 Participants	0 Participants n=22 Participants	19 Participants n=19 Participants	0 Participants n=19 Participants	65 Participants n=130 Participants
Age, Categorical >=65 years	0 Participants n=24 Participants	0 Participants n=24 Participants	0 Participants n=22 Participants	0 Participants n=22 Participants	0 Participants n=19 Participants	0 Participants n=19 Participants	0 Participants n=130 Participants
Age, Continuous	35.75 years STANDARD_DEVIATION 7.56 • n=24 Participants • One family withdrew from IRS control group after random assignment due to displeasure at group assignment and asked for data to be removed.	3.80 years STANDARD_DEVIATION 1.55 • n=24 Participants • One family withdrew from IRS control group after random assignment due to displeasure at group assignment and asked for data to be removed.	35.32 years STANDARD_DEVIATION 4.04 • n=22 Participants • One family withdrew from IRS control group after random assignment due to displeasure at group assignment and asked for data to be removed.	3.99 years STANDARD_DEVIATION 1.55 • n=22 Participants • One family withdrew from IRS control group after random assignment due to displeasure at group assignment and asked for data to be removed.	34.56 years STANDARD_DEVIATION 6.05 • n=18 Participants • One family withdrew from IRS control group after random assignment due to displeasure at group assignment and asked for data to be removed.	4.01 years STANDARD_DEVIATION 1.55 • n=18 Participants • One family withdrew from IRS control group after random assignment due to displeasure at group assignment and asked for data to be removed.	19.60 years STANDARD_DEVIATION 3.74 • n=128 Participants • One family withdrew from IRS control group after random assignment due to displeasure at group assignment and asked for data to be removed.
Sex: Female, Male Female	20 Participants n=24 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	9 Participants n=24 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	17 Participants n=22 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	5 Participants n=22 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	17 Participants n=18 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	1 Participants n=18 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	69 Participants n=128 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.
Sex: Female, Male Male	4 Participants n=24 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	15 Participants n=24 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	5 Participants n=22 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	17 Participants n=22 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	1 Participants n=18 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	17 Participants n=18 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	59 Participants n=128 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.
Race/Ethnicity, Customized Minoritized Race or Ethnicity	7 Participants n=24 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	7 Participants n=24 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	5 Participants n=22 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	10 Participants n=22 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	4 Participants n=18 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	5 Participants n=18 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.	38 Participants n=128 Participants • One family withdrew from the study after group assignment to IRS Control condition due to dissatisfaction with group assignment and requested all data to be withdrawn.
Region of Enrollment United States	24 participants n=24 Participants	24 participants n=24 Participants	22 participants n=22 Participants	22 participants n=22 Participants	19 participants n=19 Participants	19 participants n=19 Participants	130 participants n=130 Participants

PRIMARY outcome

Timeframe: Post-treatment (6 months)

Population: Analysis of parent data

Parents' use of the intervention strategies with their child is measured during a parent-child interaction in the home using the Project ImPACT Intervention Fidelity Checklist (Ingersoll \& Dvortcsak, 2019). Parents are asked to (1) play with their child for 10 minutes with a standard set of toys; and (2) have a small snack or meal with their child for 10 minutes. Parents are instructed to interact with their child as they typically would during both activities. Coders rated the parents' use of each of the five Project ImPACT intervention strategies on a scale of 1 ("does not implement the strategy, or almost all attempts to use the strategy are incorrect.") to 5 ("implements the strategy effectively throughout the session"). Scores for each strategy were averaged to form an overall fidelity rating for each activity. Fidelity ratings for each activity were averaged to form the parent fidelity variable.

Outcome measures

Outcome measures
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Parent: Information and Resource Support Control Group n=18 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.
Project ImPACT Intervention Fidelity Checklist	2.95 score on a scale Standard Error .15	3.62 score on a scale Standard Error .16	2.83 score on a scale Standard Error .18

PRIMARY outcome

Timeframe: Follow up (9 months)

Population: Analysis of parent data

Parents' use of the intervention strategies with their child is measured during a parent-child interaction in the home using the Project ImPACT Intervention Fidelity Checklist (Ingersoll \& Dvortcsak, 2019). Parents are asked to (1) play with their child for 10 minutes with a standard set of toys; and (2) have a small snack or meal with their child for 10 minutes. Parents are instructed to interact with their child as they typically would during both activities. Coders rated the parents' use of each of the five Project ImPACT intervention strategies on a scale of 1 ("does not implement the strategy, or almost all attempts to use the strategy are incorrect.") to 5 ("implements the strategy effectively throughout the session"). Scores for each strategy were averaged to form an overall fidelity rating for each activity. Fidelity ratings for each activity were averaged to form the parent fidelity variable.

Outcome measures

Outcome measures
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Parent: Information and Resource Support Control Group n=18 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.
Project ImPACT Intervention Fidelity Checklist	3.12 score on a scale Standard Error .16	3.81 score on a scale Standard Error .16	2.89 score on a scale Standard Error .19

PRIMARY outcome

Timeframe: Post-Treatment (6 months)

The PSOC measures the extent to which parents believe they have the skills and knowledge needed to be good parents (efficacy) and their perceptions regarding the value of parenthood (satisfaction). Parents rated 17 items from 1 ("Strongly disagree") to 6 ("Strongly agree"). Items are summed, with higher scores indicative of higher parenting self-efficacy. Scores can range from 17 to 102, with higher scores indicative of greater self-efficacy

Outcome measures

Outcome measures
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Parent: Information and Resource Support Control Group n=18 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.
Parent Sense of Competence (PSOC)	74.06 score on a scale Standard Error 2.41	74.45 score on a scale Standard Error 2.44	70.76 score on a scale Standard Error 2.91

PRIMARY outcome

Timeframe: Follow up (9 months)

The PSOC measures the extent to which parents believe they have the skills and knowledge needed to be good parents (efficacy) and their perceptions regarding the value of parenthood (satisfaction). Parents rated 17 items from 1 ("Strongly disagree") to 6 ("Strongly agree"). Items are summed, scores can range from 17 to 102, with higher scores indicative of higher parenting self-efficacy.

Outcome measures

Outcome measures
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Parent: Information and Resource Support Control Group n=18 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.
Parent Sense of Competence (PSOC)	72.13 score on a scale Standard Error 2.37	73.15 score on a scale Standard Error 2.44	69.09 score on a scale Standard Error 2.78

PRIMARY outcome

Timeframe: Post-treatment (6 months)

Children's use of intentional communication is scored from a parent-child interaction during play and snack using a modified version of the Weighted Frequency of Intentional Communication (WFIC) coding scheme (Yoder et al., 2021a), which quantifies the maturity of the form and frequency of intentional communication in young children with social communication delays. Coders transcribed and coded all non-imitated communicative utterances, including gestures, contingent vocalizations, single-words, simple phrases, and sentences. Each utterance was weighted (1-4) based on its complexity. Utterances are summed to produce a weighted frequency. Weighted frequency was were converted to a rate per minute by dividing the score by the length of the video. Values were log transformed to improve normality of distribution. Values ranged from -1.30 to 1.57 with higher values indicated higher weighted frequency of intentional communication. Means are adjusted for their T1 measure.

Outcome measures

Outcome measures
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Parent: Information and Resource Support Control Group n=18 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.
Weighted Frequency of Intentional Communication	.62 log(utterances per minute) Standard Error .07	.64 log(utterances per minute) Standard Error .07	.64 log(utterances per minute) Standard Error .08

PRIMARY outcome

Timeframe: Follow up (9 months)

Equally weighted composite score of child expressive language ability derived from MacArthur Bates Communicative Development Inventory (MB-CDI), Mullen Scales of Early Learning (MSEL) Expressive Language raw score, and Vineland Adaptive Behavior Scales (VABS) Expressive Language raw score. Measures were z-score transformed and averaged. Z-score of 0 represents mean for the participants. Positive z-score represent a better outcome.

Outcome measures

Outcome measures
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Parent: Information and Resource Support Control Group n=18 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.
Child Expressive Language Ability	.08 units on a scale Standard Error .12	-.05 units on a scale Standard Error .12	-.04 units on a scale Standard Error .13

SECONDARY outcome

Timeframe: Post-Treatment (6 months)

Parents complete the 8-item Positive Impact subscale of the Family Impact Questionnaire (FIQ; Donenberg \& Baker, 1993) as a measure of their perception of their child's positive impact on their experience as a parent. Parents endorsed items comparing their experience with their child to parents with same-aged typically-developing peers on a 4-point scale; higher sum scores indicate greater positive impact. Scores could range from 8 to 32.

Outcome measures

Outcome measures
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Parent: Information and Resource Support Control Group n=18 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.
Family Impact Questionnaire	22 units on a scale Standard Error 1.34	23.08 units on a scale Standard Error 1.16	20.18 units on a scale Standard Error 1.36

SECONDARY outcome

Timeframe: Post-Treatment (6 months)

Parents complete the Parenting Stress Index, Short Form (PSI-SF; Abidin, 1995), a 36-item measure of parenting stress. Parents rated items on a 5-point scale. Items are summed with higher scores indicating greater parenting stress. The Total Stress scale was used as a measure of parenting stress. Raw Scores could range from 36 to 180.

Outcome measures

Outcome measures
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Parent: Information and Resource Support Control Group n=18 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.
Parenting Stress Index-Short Form	92.69 score on a scale Standard Error 4.33	90.76 score on a scale Standard Error 4.39	97.50 score on a scale Standard Error 5.20

SECONDARY outcome

Timeframe: Follow up (9 months)

The Mullen Scales of Early Learning (MSEL; Mullen, 1995) is a standardized developmental test for young children that assesses skills in expressive language, receptive language, visual reception, and fine motor. The raw score for the Expressive Language scale was used in analyses. Raw scores ranged from 7 to 47. Higher scores indicate better language outcomes. Means are adjusted for their T1 measure.

Outcome measures

Outcome measures
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Parent: Information and Resource Support Control Group n=18 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.
Mullen Scales of Early Learning	23.88 score on a scale Standard Error 1.40	22.71 score on a scale Standard Error 1.90	23.12 score on a scale Standard Error 1.46

SECONDARY outcome

Timeframe: Follow up (9 Months)

MacArthur-Bates Communicative Development Inventory (MCDI; Fenson et al., 2006) is a parent report instrument that measures early language development, including productive vocabulary. Parents complete either the Words and Gestures Form or Words and Sentences Form, depending on their child's predominant method of communication online. The total number of words parents reported that their child "understands and says" (Words and Gestures Form) or "words produced" (Words and Sentences Form) is used in analyses. Means are adjusted for their T1 measures

Outcome measures

Outcome measures
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Parent: Information and Resource Support Control Group n=18 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.
MacArthur-Bates Communicative Development Inventory	328.68 number of words Standard Error 31.38	270.52 number of words Standard Error 33.21	282.85 number of words Standard Error 36.73

SECONDARY outcome

Timeframe: Follow up (9 Months)

The VABS is a standardized parent interview that assesses adaptive functioning in four domains: communication, socialization, daily living skills, and motor skills. The raw score for the Expressive Language subdomain was used in analyses. Raw scores ranged from 10 to 99. Higher scores indicate better language outcomes. Means are adjusted for their T1 measures

Outcome measures

Outcome measures
Measure	Parent: Self-Directed Group n=24 Participants Parent participants assigned to the self-directed group will receive access to the secure, password-protected, ImPACT Online web-based program for four months. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. The web application contains 12, self-directed lessons, each of which takes approximately 75 minutes to complete. Parent participants will be encouraged to complete one lesson per week and to practice the intervention techniques with their child between each lesson. Each lesson consists of a Narrated Slideshow with embedded video clips, a Written Manual, a self-check quiz, short interactive exercises, a Homework Plan, and reflection questions. Parent participants in the self-directed group may contact project staff via phone or email for assistance with technology-related problems (e.g., difficulty with logins, problems playing video). However, they will receive no assistance or support in learning the intervention from project staff outside of the self-directed web-based program.	Parent: Therapist-Assisted Group n=22 Participants Parent participants assigned to the therapist-assisted group will be given access to the ImPACT Online web-based program for four months and will be encouraged to work through the program at the same pace as the self-directed group. The intervention content was adapted from Project ImPACT, a manualized NDBI parent training curriculum. Parent participants will also receive 2, 30-minute remote coaching sessions per week (24 total sessions) via video conferencing software by a trained therapist to assist them in learning the intervention. The first coaching session of the week will involve the coach and participant and will be used to help clarify the content of the relevant lesson and help the parent participant apply the lesson content to their own child. The second coaching session of the week will involve the coach, participant, and child and will be used to provide the participant with "live" feedback on their use of the intervention techniques as they practice with their child.	Parent: Information and Resource Support Control Group n=18 Participants Parent participants assigned to the web-based information control group will be given access the Resources page with links to the same ASD information websites, but will not receive access to other aspect of the ImPACT Online program. This condition will be used to control for child participant maturation as well as the potentially confounding effect of parent participants having access to autism-related information via the internet.
Vineland Adaptive Behavior Scales, 2nd Edition	48.04 score on a scale Standard Error 2.61	46.39 score on a scale Standard Error 2.72	44.30 score on a scale Standard Error 3.01

OTHER_PRE_SPECIFIED outcome

Timeframe: Post-treatment (6 months)

ImPACT Online electronic tracking system. % of learning activities accessed