Trial Outcomes & Findings for Testing a Brief Substance Misuse Preventative Intervention for Parents/Guardians of 5th-7th Grade Students (NCT NCT03925220)

Last Updated: 2025-07-09

Results Overview

Positive and negative expectancies about the affective, cognitive, and behavioral effects of cigarette use will be assessed with the Positive and Negative Outcome Expectancies of Smoking scale. The tool comprises 12 items, each with response options ranging from (1) Strongly Disagree to (6) Strongly Agree. The tool has two subscales (positive expectancies, determined by 7 questions; negative expectancies, determined by 5 questions). Summary scores for both the positive and negative expectancies are created. Summary score values range from 0-7 for positive, 0-5 for negative expectancies. Higher score on positive expectancies scale indicates a greater belief that there are positive outcomes of smoking. Higher score on negative expectancies scale indicates a greater belief in negative consequences of smoking. This measure was reported by children only.

Recruitment status

COMPLETED

Study phase

Target enrollment

402 participants

Primary outcome timeframe

18 months

Results posted on

2025-07-09

Participant Flow

The protocol enrollment reflects the number of parent and child dyads enrolled in the study. Before COVID-19, participants were recruited through schools. After COVID-19, participants were recruited through community-based organizations and an online recruitment company.

Participants were screened for eligibility and had to complete all baseline assessments. Parents and children were eligible to participate if: (1) the child was enrolled in 5th, 6th, or 7th grade at a school within Massachusetts at the time of recruitment, (2) the child and parent were able to independently complete study activities in English or Spanish, (3) the parent and child were living together at least 50% of the time, (4) parents consent to participate and child gives assent.

Participant milestones

Participant milestones
Measure	Substance Use Prevention Intervention - Parents Parents were given a handbook specific to the gender of their child that provides information and advice on communication and substance use prevention. Parents then participated in a one-hour session with an interventionist where the main points in the handbook were reviewed and they filled out an action plan on how to make changes in communication about substances with their child. The interventionist also provided parents with a referral packet. Two weeks after the live session, participants had a half-hour follow-up phone call with the same study interventionist. For the home-based component, parents received two messages each week with reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Substance Use Prevention Intervention - Children Children discussed with their parents a handbook specific to their gender that provides information and advice on communication and substance use prevention. Children participated with their parents in completing an action plan on how to make changes in communication about substances. Children received reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Nutrition, Physical Activity, and Weight Talk Comparison - Parents Parents received a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Parents also received a magnet with a message about nutrition and exercise. To control for contact time, these participants met live with a study staff member two weeks after receiving the handbook, completed an action plan, and had the 30-minute call, as well as receive two text messages twice per week for 13 weeks with tips and reminders from the comparison handbook and insert.	Nutrition, Physical Activity, and Weight Talk Comparison - Children Children discussed with their parents a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Participants also received a magnet with a message about nutrition and exercise. Children also helped their parents complete an action plan and received tips and reminders from the comparison handbook and insert.
Overall Study STARTED	201	201	201	201
Overall Study Baseline Analyzed	192	192	196	196
Overall Study 3 Months Follow-up	181	181	185	185
Overall Study 6 Months Follow-up	159	159	170	170
Overall Study 12 Months Follow-up	152	148	150	150
Overall Study 18 Months Follow-up	157	151	160	159
Overall Study COMPLETED	157	151	160	159
Overall Study NOT COMPLETED	44	50	41	42

Reasons for withdrawal

Reasons for withdrawal
Measure	Substance Use Prevention Intervention - Parents Parents were given a handbook specific to the gender of their child that provides information and advice on communication and substance use prevention. Parents then participated in a one-hour session with an interventionist where the main points in the handbook were reviewed and they filled out an action plan on how to make changes in communication about substances with their child. The interventionist also provided parents with a referral packet. Two weeks after the live session, participants had a half-hour follow-up phone call with the same study interventionist. For the home-based component, parents received two messages each week with reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Substance Use Prevention Intervention - Children Children discussed with their parents a handbook specific to their gender that provides information and advice on communication and substance use prevention. Children participated with their parents in completing an action plan on how to make changes in communication about substances. Children received reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Nutrition, Physical Activity, and Weight Talk Comparison - Parents Parents received a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Parents also received a magnet with a message about nutrition and exercise. To control for contact time, these participants met live with a study staff member two weeks after receiving the handbook, completed an action plan, and had the 30-minute call, as well as receive two text messages twice per week for 13 weeks with tips and reminders from the comparison handbook and insert.	Nutrition, Physical Activity, and Weight Talk Comparison - Children Children discussed with their parents a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Participants also received a magnet with a message about nutrition and exercise. Children also helped their parents complete an action plan and received tips and reminders from the comparison handbook and insert.
Overall Study Withdrawal by Subject	4	4	4	4
Overall Study Lost to Follow-up	40	46	37	38

Baseline Characteristics

Missing participants did not answer the survey question.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Substance Use Prevention Intervention n=192 Participants Parents were given a handbook specific to the gender of their child that provides information and advice communication and substance use prevention. Parents then participated in a one-hour session with an interventionist where the main points in the handbook were reviewed and they filled out an action plan on how to make changes in communication about substances with their child. The interventionist also provided parents with a referral packet. Two weeks after the live session, participants had a half-hour follow-up phone call with the same study interventionist. For the home-based component, parents received two messages each week with reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Substance Use Prevention Intervention - Children n=192 Participants Children discussed with their parents a handbook specific to their gender that provides information and advice on communication and substance use prevention. Children participated with their parents in completing an action plan on how to make changes in communication about substances. Children received reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Nutrition, Physical Activity, and Weight Talk Comparison n=196 Participants For the comparison condition, after the baseline assessment, parents received a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Parents also received a magnet with a message about nutrition and exercise. To control for contact time, these participants met live with a study staff member two weeks after receiving the handbook, completed an action plan, and had the 30-minute call, as well as receive two text messages twice per week for 13 weeks with tips and reminders from the comparison handbook and insert.	Nutrition, Physical Activity, and Weight Talk Comparison - Children n=196 Participants Children discussed with their parents a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Participants also received a magnet with a message about nutrition and exercise. Children also helped their parents complete an action plan and received tips and reminders from the comparison handbook and insert.	Total n=776 Participants Total of all reporting groups
Frequency of parent-child conversations on substances On using cannabis · 'Several times' or 'a lot'	16 Participants n=5 Participants • Missing participants did not answer the survey question.	14 Participants n=7 Participants • Missing participants did not answer the survey question.	27 Participants n=5 Participants • Missing participants did not answer the survey question.	18 Participants n=4 Participants • Missing participants did not answer the survey question.	75 Participants n=21 Participants • Missing participants did not answer the survey question.
Frequency of parent-child conversations on substances On using cannabis · 'None', 'once', or 'a few times'	176 Participants n=5 Participants • Missing participants did not answer the survey question.	178 Participants n=7 Participants • Missing participants did not answer the survey question.	169 Participants n=5 Participants • Missing participants did not answer the survey question.	178 Participants n=4 Participants • Missing participants did not answer the survey question.	701 Participants n=21 Participants • Missing participants did not answer the survey question.
Age, Continuous	42.1 years STANDARD_DEVIATION 6.3 • n=5 Participants	11.8 years STANDARD_DEVIATION 1.1 • n=7 Participants	43.3 years STANDARD_DEVIATION 6.8 • n=5 Participants	11.8 years STANDARD_DEVIATION 1.0 • n=4 Participants	27.3 years STANDARD_DEVIATION 3.8 • n=21 Participants
Sex: Female, Male Female	169 Participants n=5 Participants	99 Participants n=7 Participants	173 Participants n=5 Participants	102 Participants n=4 Participants	543 Participants n=21 Participants
Sex: Female, Male Male	23 Participants n=5 Participants	93 Participants n=7 Participants	23 Participants n=5 Participants	94 Participants n=4 Participants	233 Participants n=21 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	41 Participants n=5 Participants	48 Participants n=7 Participants	40 Participants n=5 Participants	42 Participants n=4 Participants	171 Participants n=21 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	151 Participants n=5 Participants	144 Participants n=7 Participants	156 Participants n=5 Participants	154 Participants n=4 Participants	605 Participants n=21 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants
Race (NIH/OMB) Asian	8 Participants n=5 Participants	9 Participants n=7 Participants	7 Participants n=5 Participants	4 Participants n=4 Participants	28 Participants n=21 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants	1 Participants n=4 Participants	3 Participants n=21 Participants
Race (NIH/OMB) Black or African American	19 Participants n=5 Participants	21 Participants n=7 Participants	26 Participants n=5 Participants	28 Participants n=4 Participants	94 Participants n=21 Participants
Race (NIH/OMB) White	117 Participants n=5 Participants	104 Participants n=7 Participants	118 Participants n=5 Participants	110 Participants n=4 Participants	449 Participants n=21 Participants
Race (NIH/OMB) More than one race	7 Participants n=5 Participants	9 Participants n=7 Participants	4 Participants n=5 Participants	11 Participants n=4 Participants	31 Participants n=21 Participants
Race (NIH/OMB) Unknown or Not Reported	41 Participants n=5 Participants	48 Participants n=7 Participants	40 Participants n=5 Participants	42 Participants n=4 Participants	171 Participants n=21 Participants
Region of Enrollment United States	192 Participants n=5 Participants	192 Participants n=7 Participants	196 Participants n=5 Participants	196 Participants n=4 Participants	776 Participants n=21 Participants
Frequency of parent-child conversations on substances On drinking alcohol · 'Several times' or 'a lot'	28 Participants n=5 Participants • Missing participants did not answer the survey question.	17 Participants n=7 Participants • Missing participants did not answer the survey question.	36 Participants n=5 Participants • Missing participants did not answer the survey question.	23 Participants n=4 Participants • Missing participants did not answer the survey question.	104 Participants n=21 Participants • Missing participants did not answer the survey question.
Frequency of parent-child conversations on substances On drinking alcohol · 'None', 'once', or 'a few times'	164 Participants n=5 Participants • Missing participants did not answer the survey question.	175 Participants n=7 Participants • Missing participants did not answer the survey question.	160 Participants n=5 Participants • Missing participants did not answer the survey question.	173 Participants n=4 Participants • Missing participants did not answer the survey question.	672 Participants n=21 Participants • Missing participants did not answer the survey question.
Frequency of parent-child conversations on substances On smoking cigarettes · 'Several times' or 'a lot'	23 Participants n=5 Participants • Missing participants did not answer the survey question.	12 Participants n=7 Participants • Missing participants did not answer the survey question.	26 Participants n=5 Participants • Missing participants did not answer the survey question.	19 Participants n=4 Participants • Missing participants did not answer the survey question.	80 Participants n=21 Participants • Missing participants did not answer the survey question.
Frequency of parent-child conversations on substances On smoking cigarettes · 'None', 'once', or 'a few times'	169 Participants n=5 Participants • Missing participants did not answer the survey question.	180 Participants n=7 Participants • Missing participants did not answer the survey question.	170 Participants n=5 Participants • Missing participants did not answer the survey question.	177 Participants n=4 Participants • Missing participants did not answer the survey question.	696 Participants n=21 Participants • Missing participants did not answer the survey question.
Frequency of parent-child conversations on substances On vaping · 'Several times' or 'a lot'	19 Participants n=5 Participants • Missing participants did not answer the survey question.	14 Participants n=7 Participants • Missing participants did not answer the survey question.	31 Participants n=5 Participants • Missing participants did not answer the survey question.	13 Participants n=4 Participants • Missing participants did not answer the survey question.	77 Participants n=21 Participants • Missing participants did not answer the survey question.
Frequency of parent-child conversations on substances On vaping · 'None', 'once', or 'a few times'	173 Participants n=5 Participants • Missing participants did not answer the survey question.	178 Participants n=7 Participants • Missing participants did not answer the survey question.	165 Participants n=5 Participants • Missing participants did not answer the survey question.	183 Participants n=4 Participants • Missing participants did not answer the survey question.	699 Participants n=21 Participants • Missing participants did not answer the survey question.
Frequency of parent-child conversations on substances On using other drugs · 'Several times' or 'a lot'	23 Participants n=5 Participants • Missing participants did not answer the survey question.	17 Participants n=7 Participants • Missing participants did not answer the survey question.	23 Participants n=5 Participants • Missing participants did not answer the survey question.	25 Participants n=4 Participants • Missing participants did not answer the survey question.	88 Participants n=21 Participants • Missing participants did not answer the survey question.
Frequency of parent-child conversations on substances On using other drugs · 'None', 'once', or 'a few times'	169 Participants n=5 Participants • Missing participants did not answer the survey question.	175 Participants n=7 Participants • Missing participants did not answer the survey question.	173 Participants n=5 Participants • Missing participants did not answer the survey question.	171 Participants n=4 Participants • Missing participants did not answer the survey question.	688 Participants n=21 Participants • Missing participants did not answer the survey question.
Targeted parent-child communication on substance use Warned about the dangers · Agree	142 Participants n=5 Participants	164 Participants n=7 Participants	157 Participants n=5 Participants	168 Participants n=4 Participants	631 Participants n=21 Participants
Targeted parent-child communication on substance use Warned about the dangers · Disagree	50 Participants n=5 Participants	28 Participants n=7 Participants	39 Participants n=5 Participants	28 Participants n=4 Participants	145 Participants n=21 Participants
Targeted parent-child communication on substance use Talked about how to handle offers · Agree	81 Participants n=5 Participants	122 Participants n=7 Participants	88 Participants n=5 Participants	116 Participants n=4 Participants	407 Participants n=21 Participants
Targeted parent-child communication on substance use Talked about how to handle offers · Disagree	111 Participants n=5 Participants	70 Participants n=7 Participants	108 Participants n=5 Participants	80 Participants n=4 Participants	369 Participants n=21 Participants
Targeted parent-child communication on substance use Given rules to obey · Agree	72 Participants n=5 Participants	115 Participants n=7 Participants	82 Participants n=5 Participants	111 Participants n=4 Participants	380 Participants n=21 Participants
Targeted parent-child communication on substance use Given rules to obey · Disagree	120 Participants n=5 Participants	77 Participants n=7 Participants	114 Participants n=5 Participants	85 Participants n=4 Participants	396 Participants n=21 Participants
Targeted parent-child communication on substance use Not directly talked but given hints · Agree	44 Participants n=5 Participants	58 Participants n=7 Participants	41 Participants n=5 Participants	64 Participants n=4 Participants	207 Participants n=21 Participants
Targeted parent-child communication on substance use Not directly talked but given hints · Disagree	148 Participants n=5 Participants	134 Participants n=7 Participants	155 Participants n=5 Participants	132 Participants n=4 Participants	569 Participants n=21 Participants
Targeted parent-child communication on substance use Lectured or given speech · Agree	69 Participants n=5 Participants	84 Participants n=7 Participants	66 Participants n=5 Participants	88 Participants n=4 Participants	307 Participants n=21 Participants
Targeted parent-child communication on substance use Lectured or given speech · Disagree	123 Participants n=5 Participants	108 Participants n=7 Participants	130 Participants n=5 Participants	108 Participants n=4 Participants	469 Participants n=21 Participants
Targeted parent-child communication on substance use Made a comment on character on TV · Agree	69 Participants n=5 Participants	70 Participants n=7 Participants	78 Participants n=5 Participants	73 Participants n=4 Participants	290 Participants n=21 Participants
Targeted parent-child communication on substance use Made a comment on character on TV · Disagree	123 Participants n=5 Participants	122 Participants n=7 Participants	118 Participants n=5 Participants	123 Participants n=4 Participants	486 Participants n=21 Participants
Targeted parent-child communication on substance use Told stories of people · Agree	104 Participants n=5 Participants	58 Participants n=7 Participants	104 Participants n=5 Participants	75 Participants n=4 Participants	341 Participants n=21 Participants
Targeted parent-child communication on substance use Told stories of people · Disagree	88 Participants n=5 Participants	134 Participants n=7 Participants	92 Participants n=5 Participants	121 Participants n=4 Participants	435 Participants n=21 Participants
Targeted parent-child communication on substance use Told they would be disappointed · Agree	49 Participants n=5 Participants	91 Participants n=7 Participants	57 Participants n=5 Participants	95 Participants n=4 Participants	292 Participants n=21 Participants
Targeted parent-child communication on substance use Told they would be disappointed · Disagree	143 Participants n=5 Participants	101 Participants n=7 Participants	139 Participants n=5 Participants	101 Participants n=4 Participants	484 Participants n=21 Participants
Targeted parent-child communication on substance use Shown information about the dangers · Agree	53 Participants n=5 Participants	50 Participants n=7 Participants	47 Participants n=5 Participants	59 Participants n=4 Participants	209 Participants n=21 Participants
Targeted parent-child communication on substance use Shown information about the dangers · Disagree	139 Participants n=5 Participants	142 Participants n=7 Participants	149 Participants n=5 Participants	137 Participants n=4 Participants	567 Participants n=21 Participants
Targeted parent-child communication on substance use Asked about their thoughts/opinions · Agree	102 Participants n=5 Participants	106 Participants n=7 Participants	107 Participants n=5 Participants	115 Participants n=4 Participants	430 Participants n=21 Participants
Targeted parent-child communication on substance use Asked about their thoughts/opinions · Disagree	90 Participants n=5 Participants	86 Participants n=7 Participants	89 Participants n=5 Participants	81 Participants n=4 Participants	346 Participants n=21 Participants

PRIMARY outcome

Timeframe: 3 months (short-term) and 18 months (long-term)

Population: Sample sizes differ for parent- and child-reported data based on how many parents and children completed the survey at each follow-up.

Frequency of conversations was measured using an item adapted from a measure for parent-child communication about sex (Miller et al, 1998). Question: "During the past 3-months, how many times have you and your child talked about \[substance\]?" The same question assessed frequency for each substance of interest (alcohol, cigarettes, e-cigarettes, cannabis, other drugs) on a five-point Likert scale from "None" to "A lot". Responses were dichotomized as "Several" or "A lot" versus "None", "Once", or "A few times". This measure was reported by parents and children.

Outcome measures

Outcome measures
Measure	Substance Use Prevention Intervention n=178 Participants Parents were given a handbook specific to the gender of their child that provides information and advice communication and substance use prevention. Parents then participated in a one-hour session with an interventionist where the main points in the handbook were reviewed and they filled out an action plan on how to make changes in communication about substances with their child. The interventionist also provided parents with a referral packet. Two weeks after the live session, participants had a half-hour follow-up phone call with the same study interventionist. For the home-based component, parents received two messages each week with reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Substance Use Prevention Intervention - Children n=178 Participants Children discussed with their parents a handbook specific to their gender that provides information and advice on communication and substance use prevention. Children participated with their parents in completing an action plan on how to make changes in communication about substances. Children received reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Nutrition, Physical Activity, and Weight Talk Comparison n=185 Participants For the comparison condition, after the baseline assessment, parents received a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Parents also received a magnet with a message about nutrition and exercise. To control for contact time, these participants met live with a study staff member two weeks after receiving the handbook, completed an action plan, and had the 30-minute call, as well as receive two text messages twice per week for 13 weeks with tips and reminders from the comparison handbook and insert.	Nutrition, Physical Activity, and Weight Talk Comparison - Children n=185 Participants Children discussed with their parents a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Participants also received a magnet with a message about nutrition and exercise. Children also helped their parents complete an action plan and received tips and reminders from the comparison handbook and insert.
Frequency of Parent-child Conversations on Substances 3-months - drinking alcohol · 'Several times' or 'a lot'	87 Participants	32 Participants	29 Participants	20 Participants
Frequency of Parent-child Conversations on Substances 3-months - drinking alcohol · 'None', 'once', or 'a few times'	91 Participants	146 Participants	156 Participants	165 Participants
Frequency of Parent-child Conversations on Substances 3-months - using e-cigarettes or vaping · 'Several times' or 'a lot'	70 Participants	28 Participants	28 Participants	17 Participants
Frequency of Parent-child Conversations on Substances 3-months - using e-cigarettes or vaping · 'None', 'once', or 'a few times'	108 Participants	150 Participants	157 Participants	168 Participants
Frequency of Parent-child Conversations on Substances 3-months - using marijuana · 'Several times' or 'a lot'	61 Participants	20 Participants	27 Participants	17 Participants
Frequency of Parent-child Conversations on Substances 3-months - using marijuana · 'None', 'once', or 'a few times'	117 Participants	158 Participants	158 Participants	168 Participants
Frequency of Parent-child Conversations on Substances 3-months - smoking cigarettes · 'Several times' or 'a lot'	79 Participants	28 Participants	23 Participants	21 Participants
Frequency of Parent-child Conversations on Substances 3-months - smoking cigarettes · 'None', 'once', or 'a few times'	99 Participants	150 Participants	162 Participants	164 Participants
Frequency of Parent-child Conversations on Substances 3-months - using other drugs · 'Several times' or 'a lot'	55 Participants	25 Participants	20 Participants	19 Participants
Frequency of Parent-child Conversations on Substances 3-months - using other drugs · 'None', 'once', or 'a few times'	123 Participants	153 Participants	165 Participants	166 Participants
Frequency of Parent-child Conversations on Substances 18-months - drinking alcohol · 'Several times' or 'a lot'	51 Participants	30 Participants	36 Participants	28 Participants
Frequency of Parent-child Conversations on Substances 18-months - drinking alcohol · 'None', 'once', or 'a few times'	106 Participants	121 Participants	124 Participants	131 Participants
Frequency of Parent-child Conversations on Substances 18-months - using e-cigarettes or vaping · 'Several times' or 'a lot'	40 Participants	22 Participants	33 Participants	18 Participants
Frequency of Parent-child Conversations on Substances 18-months - using e-cigarettes or vaping · 'None', 'once', or 'a few times'	117 Participants	129 Participants	127 Participants	141 Participants
Frequency of Parent-child Conversations on Substances 18-months - using marijuana · 'Several times' or 'a lot'	38 Participants	26 Participants	30 Participants	22 Participants
Frequency of Parent-child Conversations on Substances 18-months - using marijuana · 'None', 'once', or 'a few times'	119 Participants	125 Participants	130 Participants	137 Participants
Frequency of Parent-child Conversations on Substances 18-months - smoking cigarettes · 'Several times' or 'a lot'	33 Participants	22 Participants	28 Participants	18 Participants
Frequency of Parent-child Conversations on Substances 18-months - smoking cigarettes · 'None', 'once', or 'a few times'	124 Participants	129 Participants	132 Participants	141 Participants
Frequency of Parent-child Conversations on Substances 18-months - using other drugs · 'Several times' or 'a lot'	28 Participants	23 Participants	26 Participants	19 Participants
Frequency of Parent-child Conversations on Substances 18-months - using other drugs · 'None', 'once', or 'a few times'	129 Participants	128 Participants	134 Participants	140 Participants

PRIMARY outcome

Timeframe: 3 months (short-term) and 18 months (long-term)

Population: Sample sizes differ for parent- and child-reported data based on how many parents and children completed the survey at each follow-up.

An adapted version of the Targeted Parent-Child Communication about Alcohol Scale (Miller-Day et al, 2010) was used to assess targeted communication about alcohol and other drugs use. The ten-item assesses parents' agreement on having communication about substance use related topics and applying strategies parents may have discussed with their child. Items were assessed on a six-point Likert scale from "Strongly agree" to "Strongly disagree". Responses were dichotomized as "Agree" or "Strongly Agree" versus "Strongly Disagree" to "Somewhat Agree". This measure was reported by parents and children.

Outcome measures

Outcome measures
Measure	Substance Use Prevention Intervention n=181 Participants Parents were given a handbook specific to the gender of their child that provides information and advice communication and substance use prevention. Parents then participated in a one-hour session with an interventionist where the main points in the handbook were reviewed and they filled out an action plan on how to make changes in communication about substances with their child. The interventionist also provided parents with a referral packet. Two weeks after the live session, participants had a half-hour follow-up phone call with the same study interventionist. For the home-based component, parents received two messages each week with reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Substance Use Prevention Intervention - Children n=181 Participants Children discussed with their parents a handbook specific to their gender that provides information and advice on communication and substance use prevention. Children participated with their parents in completing an action plan on how to make changes in communication about substances. Children received reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Nutrition, Physical Activity, and Weight Talk Comparison n=185 Participants For the comparison condition, after the baseline assessment, parents received a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Parents also received a magnet with a message about nutrition and exercise. To control for contact time, these participants met live with a study staff member two weeks after receiving the handbook, completed an action plan, and had the 30-minute call, as well as receive two text messages twice per week for 13 weeks with tips and reminders from the comparison handbook and insert.	Nutrition, Physical Activity, and Weight Talk Comparison - Children n=185 Participants Children discussed with their parents a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Participants also received a magnet with a message about nutrition and exercise. Children also helped their parents complete an action plan and received tips and reminders from the comparison handbook and insert.
Targeted Parent-child Communication on Substance Use 3 months - warned about the dangers · Agree	162 Participants	147 Participants	126 Participants	143 Participants
Targeted Parent-child Communication on Substance Use 3 months - warned about the dangers · Disagree	19 Participants	34 Participants	59 Participants	42 Participants
Targeted Parent-child Communication on Substance Use 3 months - talked about how to handle offers · Agree	137 Participants	125 Participants	81 Participants	106 Participants
Targeted Parent-child Communication on Substance Use 3 months - talked about how to handle offers · Disagree	44 Participants	56 Participants	104 Participants	79 Participants
Targeted Parent-child Communication on Substance Use 3 months - given rules to obey · Agree	139 Participants	111 Participants	61 Participants	104 Participants
Targeted Parent-child Communication on Substance Use 3 months - given rules to obey · Disagree	42 Participants	70 Participants	124 Participants	81 Participants
Targeted Parent-child Communication on Substance Use 3 months - not directly talked but given hints on not to use · Agree	18 Participants	39 Participants	29 Participants	59 Participants
Targeted Parent-child Communication on Substance Use 3 months - not directly talked but given hints on not to use · Disagree	163 Participants	142 Participants	156 Participants	126 Participants
Targeted Parent-child Communication on Substance Use 3 months - lectured or given speech · Agree	71 Participants	83 Participants	41 Participants	68 Participants
Targeted Parent-child Communication on Substance Use 3 months - lectured or given speech · Disagree	110 Participants	98 Participants	144 Participants	117 Participants
Targeted Parent-child Communication on Substance Use 3 months - made a comment if a character on TV is drinking/drunk · Agree	83 Participants	84 Participants	57 Participants	64 Participants
Targeted Parent-child Communication on Substance Use 3 months - made a comment if a character on TV is drinking/drunk · Disagree	98 Participants	97 Participants	128 Participants	121 Participants
Targeted Parent-child Communication on Substance Use 3 months - told stories of people who drink or have been drunk or use drugs · Agree	112 Participants	60 Participants	86 Participants	60 Participants
Targeted Parent-child Communication on Substance Use 3 months - told stories of people who drink or have been drunk or use drugs · Disagree	69 Participants	121 Participants	99 Participants	125 Participants
Targeted Parent-child Communication on Substance Use 3 months - told they would be disappointed · Agree	88 Participants	77 Participants	47 Participants	71 Participants
Targeted Parent-child Communication on Substance Use 3 months - told they would be disappointed · Disagree	93 Participants	104 Participants	138 Participants	114 Participants
Targeted Parent-child Communication on Substance Use 3 months - shown information about the dangers · Agree	71 Participants	50 Participants	48 Participants	44 Participants
Targeted Parent-child Communication on Substance Use 3 months - shown information about the dangers · Disagree	110 Participants	131 Participants	137 Participants	141 Participants
Targeted Parent-child Communication on Substance Use 3 months - asked about their thoughts or opinions · Agree	144 Participants	101 Participants	83 Participants	81 Participants
Targeted Parent-child Communication on Substance Use 3 months - asked about their thoughts or opinions · Disagree	37 Participants	80 Participants	102 Participants	104 Participants
Targeted Parent-child Communication on Substance Use 18 months - warned about the dangers · Agree	114 Participants	108 Participants	105 Participants	108 Participants
Targeted Parent-child Communication on Substance Use 18 months - warned about the dangers · Disagree	43 Participants	43 Participants	55 Participants	51 Participants
Targeted Parent-child Communication on Substance Use 18 months - talked about how to handle offers · Agree	95 Participants	93 Participants	76 Participants	81 Participants
Targeted Parent-child Communication on Substance Use 18 months - talked about how to handle offers · Disagree	62 Participants	58 Participants	84 Participants	78 Participants
Targeted Parent-child Communication on Substance Use 18 months - given rules to obey · Agree	87 Participants	92 Participants	63 Participants	74 Participants
Targeted Parent-child Communication on Substance Use 18 months - given rules to obey · Disagree	70 Participants	59 Participants	97 Participants	85 Participants
Targeted Parent-child Communication on Substance Use 18 months - not directly talked but given hints on not to use · Agree	18 Participants	22 Participants	27 Participants	49 Participants
Targeted Parent-child Communication on Substance Use 18 months - not directly talked but given hints on not to use · Disagree	139 Participants	129 Participants	133 Participants	110 Participants
Targeted Parent-child Communication on Substance Use 18 months - lectured or given speech · Agree	50 Participants	62 Participants	32 Participants	47 Participants
Targeted Parent-child Communication on Substance Use 18 months - lectured or given speech · Disagree	107 Participants	89 Participants	128 Participants	112 Participants
Targeted Parent-child Communication on Substance Use 18 months - made a comment if a character on TV is drinking/drunk · Agree	69 Participants	47 Participants	50 Participants	52 Participants
Targeted Parent-child Communication on Substance Use 18 months - made a comment if a character on TV is drinking/drunk · Disagree	88 Participants	104 Participants	110 Participants	107 Participants
Targeted Parent-child Communication on Substance Use 18 months - told stories of people who drink or have been drunk or use drugs · Agree	90 Participants	55 Participants	76 Participants	52 Participants
Targeted Parent-child Communication on Substance Use 18 months - told stories of people who drink or have been drunk or use drugs · Disagree	67 Participants	96 Participants	84 Participants	107 Participants
Targeted Parent-child Communication on Substance Use 18 months - told they would be disappointed · Agree	56 Participants	59 Participants	41 Participants	52 Participants
Targeted Parent-child Communication on Substance Use 18 months - told they would be disappointed · Disagree	101 Participants	92 Participants	119 Participants	107 Participants
Targeted Parent-child Communication on Substance Use 18 months - shown information about the dangers · Agree	56 Participants	36 Participants	38 Participants	37 Participants
Targeted Parent-child Communication on Substance Use 18 months - shown information about the dangers · Disagree	101 Participants	115 Participants	122 Participants	122 Participants
Targeted Parent-child Communication on Substance Use 18 months - asked about their thoughts or opinions · Agree	99 Participants	64 Participants	84 Participants	57 Participants
Targeted Parent-child Communication on Substance Use 18 months - asked about their thoughts or opinions · Disagree	58 Participants	87 Participants	76 Participants	102 Participants

PRIMARY outcome

Timeframe: 12 months

Population: Sample sizes differ at each follow-up based on how many parents and children completed the audio submission.

The prompts, modeled after the Family Assessment Task (FAsTask) where parents and adolescents have a conversation about substance use and related behaviors, were developed by the study team (Spirito et al, 2011). The same prompts are used at each time point. The sub-scales (expectations, messaging, communication style, and strategies) range from 1 to 9 (higher values represent a higher quality conversation compared to lower values). The overall combined score ranges from 4 to 36 (higher values represent a higher quality conversation compared to lower values).

Outcome measures

Outcome measures
Measure	Substance Use Prevention Intervention n=90 Participants Parents were given a handbook specific to the gender of their child that provides information and advice communication and substance use prevention. Parents then participated in a one-hour session with an interventionist where the main points in the handbook were reviewed and they filled out an action plan on how to make changes in communication about substances with their child. The interventionist also provided parents with a referral packet. Two weeks after the live session, participants had a half-hour follow-up phone call with the same study interventionist. For the home-based component, parents received two messages each week with reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Substance Use Prevention Intervention - Children n=86 Participants Children discussed with their parents a handbook specific to their gender that provides information and advice on communication and substance use prevention. Children participated with their parents in completing an action plan on how to make changes in communication about substances. Children received reminders and tips that reinforce the information covered in the handbook. Finally, participants received a magnet about the importance of family meals that they were instructed to put on their refrigerators.	Nutrition, Physical Activity, and Weight Talk Comparison For the comparison condition, after the baseline assessment, parents received a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Parents also received a magnet with a message about nutrition and exercise. To control for contact time, these participants met live with a study staff member two weeks after receiving the handbook, completed an action plan, and had the 30-minute call, as well as receive two text messages twice per week for 13 weeks with tips and reminders from the comparison handbook and insert.	Nutrition, Physical Activity, and Weight Talk Comparison - Children Children discussed with their parents a handbook on nutrition and physical activity entitled: "Healthy Eating \& Physical Activity Across Your Lifespan: Helping your Child - Tips for Parents". This handbook, which is adapted from the handbook developed by the National Institute of Diabetes and Digestive and Kidney Diseases and the Weight Control Information Network, is approximately the same length as the intervention handbook and is available in English and Spanish. It is given with an insert on reducing weight talk and weight teasing in the family. Participants also received a magnet with a message about nutrition and exercise. Children also helped their parents complete an action plan and received tips and reminders from the comparison handbook and insert.
Parent-child Audio-recorded Conversations About Substance Use Messaging	4.7 score Standard Deviation 1.3	4.6 score Standard Deviation 1.3	—	—
Parent-child Audio-recorded Conversations About Substance Use Expectations	3.5 score Standard Deviation 2.1	3.2 score Standard Deviation 1.9	—	—
Parent-child Audio-recorded Conversations About Substance Use Communication style	5.5 score Standard Deviation 1.6	5.5 score Standard Deviation 1.5	—	—
Parent-child Audio-recorded Conversations About Substance Use Strategies	2.4 score Standard Deviation 1.8	2.2 score Standard Deviation 1.5	—	—
Parent-child Audio-recorded Conversations About Substance Use Overall combined score	16 score Standard Deviation 4.0	15.5 score Standard Deviation 3.5	—	—

PRIMARY outcome

Timeframe: 12 months

Population: Sample sizes differ at each follow-up based on how many parents and children completed the video submission.

The mean quality of mealtime interactions is measured using various scales from the Iowa Family Interaction Rating Scales (IFIRS) coding system: Dyadic Interaction Scales, Dyadic Relationship Scales, Group Interactions Scales, and Parenting Scales. Observed behaviors from 3 video-recorded family meals are assessed and scored on a 9-point scale. A higher score indicates coders observed a higher intensity and/or frequency of the construct in the video-recorded family meals. Each IFIRS scale is scored individually, and the average across the 3 family meals is reported. The items were organized into four subscales: Communication (range: 4-36), Parenting Style (range: 5-45), Dyad Relationship (range: 5-45), and Group Enjoyment (range: 1-9).