Trial Outcomes & Findings for Measuring the Preferences of Patients With Type II Diabetes Using Best-worst Scaling and Discrete Choice Experiment (NCT NCT02637622)

NCT ID: NCT02637622

Last Updated: 2024-11-29

Results Overview

Preference estimate for each medicine attribute level from a conditional logit regression analysis. For each arm, there were six attributes of the medication, with 3 levels each. Within each attribute the parameter estimates for each of the levels sum to 0. If a parameter estimate for a level is above (below) 0 then the parameter is higher (lower) than average for that medication attribute.

Recruitment status

COMPLETED

Target enrollment

1103 participants

Primary outcome timeframe

One-time survey

Results posted on

2024-11-29

Participant Flow

The survey was conducted through GfK KnowledgePanel. Eligible members were invited by email to participate in the survey. All participants were required to be 18 years or older with self-reported physician-diagnosed type 2 diabetes and able to read English or Spanish. African Americans and Latinos were oversampled.

638 respondents (34%) did not respond to the survey and 139 people among those who responded (11%) were excluded based on the screening questions.

Participant milestones

Participant milestones
Measure
Best-Worst Scaling (Case 2)
Preference measured by best-worst scaling (case 2) Best-Worst Scaling (Case 2): Respondents receive questions asking them to choose the best and worst features of a hypothetical medication.
Discrete Choice Experiment
Preference measured by discrete choice experiment Discrete Choice Experiment: Respondents receive questions asking them to choose the medication they prefer between a pair of hypothetical medications.
Overall Study
STARTED
551
552
Overall Study
COMPLETED
551
552
Overall Study
NOT COMPLETED
0
0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Measuring the Preferences of Patients With Type II Diabetes Using Best-worst Scaling and Discrete Choice Experiment

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Best-Worst Scaling (BWS) (Case 2)
n=551 Participants
Preference measured by best-worst scaling (case 2) Best-Worst Scaling (Case 2): Respondents receive questions asking them to choose the best and worst features of a hypothetical medication.
Discrete Choice Experiment (DCE)
n=552 Participants
Preference measured by discrete choice experiment Discrete Choice Experiment: Respondents receive questions asking them to choose the medication they prefer between a pair of hypothetical medications.
Total
n=1103 Participants
Total of all reporting groups
Age, Continuous
62.55 years
n=5 Participants
61.30 years
n=7 Participants
61.93 years
n=5 Participants
Sex: Female, Male
Female
274 Participants
n=5 Participants
279 Participants
n=7 Participants
553 Participants
n=5 Participants
Sex: Female, Male
Male
277 Participants
n=5 Participants
273 Participants
n=7 Participants
550 Participants
n=5 Participants
Race/Ethnicity, Customized
White, Non-Hispanic
286 Participants
n=5 Participants
289 Participants
n=7 Participants
575 Participants
n=5 Participants
Race/Ethnicity, Customized
Black, Non-Hispanic
128 Participants
n=5 Participants
126 Participants
n=7 Participants
254 Participants
n=5 Participants
Race/Ethnicity, Customized
Other, Non-Hispanic
20 Participants
n=5 Participants
18 Participants
n=7 Participants
38 Participants
n=5 Participants
Race/Ethnicity, Customized
Hispanic
117 Participants
n=5 Participants
119 Participants
n=7 Participants
236 Participants
n=5 Participants
Region of Enrollment
United States
551 Participants
n=5 Participants
552 Participants
n=7 Participants
1103 Participants
n=5 Participants
Education
Less than high school
39 Participants
n=5 Participants
43 Participants
n=7 Participants
82 Participants
n=5 Participants
Education
High school
174 Participants
n=5 Participants
188 Participants
n=7 Participants
362 Participants
n=5 Participants
Education
Some college
182 Participants
n=5 Participants
156 Participants
n=7 Participants
338 Participants
n=5 Participants
Education
Bachelor's degree or higher
156 Participants
n=5 Participants
165 Participants
n=7 Participants
321 Participants
n=5 Participants
Income
Less than $25,000
141 Participants
n=5 Participants
132 Participants
n=7 Participants
273 Participants
n=5 Participants
Income
$25,000 - $49,999
160 Participants
n=5 Participants
148 Participants
n=7 Participants
308 Participants
n=5 Participants
Income
$50,000 - $74,999
111 Participants
n=5 Participants
111 Participants
n=7 Participants
222 Participants
n=5 Participants
Income
$75,000 and above
139 Participants
n=5 Participants
161 Participants
n=7 Participants
300 Participants
n=5 Participants
Years of diagnosis
11.47 years
STANDARD_DEVIATION 8.26 • n=5 Participants
11.24 years
STANDARD_DEVIATION 7.81 • n=7 Participants
11.35 years
STANDARD_DEVIATION 8.03 • n=5 Participants
Self-reported health
Excellent
27 Participants
n=5 Participants
33 Participants
n=7 Participants
60 Participants
n=5 Participants
Self-reported health
Very good
158 Participants
n=5 Participants
158 Participants
n=7 Participants
316 Participants
n=5 Participants
Self-reported health
Good
233 Participants
n=5 Participants
232 Participants
n=7 Participants
465 Participants
n=5 Participants
Self-reported health
Fair
103 Participants
n=5 Participants
106 Participants
n=7 Participants
209 Participants
n=5 Participants
Self-reported health
Poor
30 Participants
n=5 Participants
23 Participants
n=7 Participants
53 Participants
n=5 Participants
No. of hypoglycemic events in the past 6 months
None
278 Participants
n=5 Participants
293 Participants
n=7 Participants
571 Participants
n=5 Participants
No. of hypoglycemic events in the past 6 months
1 time
80 Participants
n=5 Participants
80 Participants
n=7 Participants
160 Participants
n=5 Participants
No. of hypoglycemic events in the past 6 months
2-5 times
144 Participants
n=5 Participants
134 Participants
n=7 Participants
278 Participants
n=5 Participants
No. of hypoglycemic events in the past 6 months
More than 5 times
49 Participants
n=5 Participants
45 Participants
n=7 Participants
94 Participants
n=5 Participants
No. of HbA1c level measured in past 6 months
None
31 Participants
n=5 Participants
41 Participants
n=7 Participants
72 Participants
n=5 Participants
No. of HbA1c level measured in past 6 months
1 time
253 Participants
n=5 Participants
239 Participants
n=7 Participants
492 Participants
n=5 Participants
No. of HbA1c level measured in past 6 months
More than 2 times
246 Participants
n=5 Participants
261 Participants
n=7 Participants
507 Participants
n=5 Participants
No. of HbA1c level measured in past 6 months
Don't know
21 Participants
n=5 Participants
11 Participants
n=7 Participants
32 Participants
n=5 Participants
Most recent HbA1c level
Over 9.0%
37 Participants
n=5 Participants
21 Participants
n=7 Participants
58 Participants
n=5 Participants
Most recent HbA1c level
Over 8.0% but under 9.0%
46 Participants
n=5 Participants
59 Participants
n=7 Participants
105 Participants
n=5 Participants
Most recent HbA1c level
Over 7.0% but under 8.0%
144 Participants
n=5 Participants
153 Participants
n=7 Participants
297 Participants
n=5 Participants
Most recent HbA1c level
Under 7.0%
232 Participants
n=5 Participants
228 Participants
n=7 Participants
460 Participants
n=5 Participants
Most recent HbA1c level
Don't know
92 Participants
n=5 Participants
91 Participants
n=7 Participants
183 Participants
n=5 Participants
Type of diabetes medicine used
No prescription medicine
62 Participants
n=5 Participants
37 Participants
n=7 Participants
99 Participants
n=5 Participants
Type of diabetes medicine used
Only pills
321 Participants
n=5 Participants
345 Participants
n=7 Participants
666 Participants
n=5 Participants
Type of diabetes medicine used
Only injections/shots
48 Participants
n=5 Participants
42 Participants
n=7 Participants
90 Participants
n=5 Participants
Type of diabetes medicine used
Pills and injections/shots
119 Participants
n=5 Participants
127 Participants
n=7 Participants
246 Participants
n=5 Participants
Type of diabetes medicine used
Refused
1 Participants
n=5 Participants
1 Participants
n=7 Participants
2 Participants
n=5 Participants
Complications
Yes
237 Participants
n=5 Participants
226 Participants
n=7 Participants
463 Participants
n=5 Participants
Complications
No
314 Participants
n=5 Participants
326 Participants
n=7 Participants
640 Participants
n=5 Participants
Other chronic conditions
Yes
461 Participants
n=5 Participants
460 Participants
n=7 Participants
921 Participants
n=5 Participants
Other chronic conditions
No
90 Participants
n=5 Participants
92 Participants
n=7 Participants
182 Participants
n=5 Participants

PRIMARY outcome

Timeframe: One-time survey

Population: Respondents who completed the survey.

Preference estimate for each medicine attribute level from a conditional logit regression analysis. For each arm, there were six attributes of the medication, with 3 levels each. Within each attribute the parameter estimates for each of the levels sum to 0. If a parameter estimate for a level is above (below) 0 then the parameter is higher (lower) than average for that medication attribute.

Outcome measures

Outcome measures
Measure
Best-Worst Scaling (Case 2)
n=551 Participants
Preference measured by best-worst scaling (case 2) survey method Best-Worst Scaling (Case 2): Respondents receive questions asking them to choose the best and worst features of a hypothetical medication.
Discrete Choice Experiment
n=552 Participants
Preference measured by discrete choice experiment Discrete Choice Experiment: Respondents receive questions asking them to choose the medication they prefer between a pair of hypothetical medications.
Patient Medication Preference as Estimated by a Choice Model
1 pill and 1 injection/day
-0.689 utility of
Interval -0.763 to -0.614
-0.805 utility of
Interval -0.911 to -0.699
Patient Medication Preference as Estimated by a Choice Model
$10 out-of-pocket cost
0.900 utility of
Interval 0.821 to 0.98
0.550 utility of
Interval 0.405 to 0.696
Patient Medication Preference as Estimated by a Choice Model
HbA1c decrease by 1%
0.983 utility of
Interval 0.903 to 1.064
0.362 utility of
Interval 0.254 to 0.47
Patient Medication Preference as Estimated by a Choice Model
HbA1c decrease by 0.5%
0.284 utility of
Interval 0.18 to 0.387
0.261 utility of
Interval 0.165 to 0.358
Patient Medication Preference as Estimated by a Choice Model
HbA1c decrease by 0%
-1.267 utility of
Interval -1.369 to -1.165
-0.623 utility of
Interval -0.724 to -0.522
Patient Medication Preference as Estimated by a Choice Model
HbA1c stable 6 days/week
0.859 utility of
Interval 0.789 to 0.928
0.395 utility of
Interval 0.303 to 0.488
Patient Medication Preference as Estimated by a Choice Model
HbA1c stable 4 days/week
-0.030 utility of
Interval -0.106 to 0.046
0.073 utility of
Interval -0.027 to 0.174
Patient Medication Preference as Estimated by a Choice Model
HbA1c stable 2 days/week
-0.828 utility of
Interval -0.894 to -0.762
-0.469 utility of
Interval -0.564 to -0.373
Patient Medication Preference as Estimated by a Choice Model
No hypoglycemia
0.640 utility of
Interval 0.562 to 0.718
0.325 utility of
Interval 0.243 to 0.406
Patient Medication Preference as Estimated by a Choice Model
Hypoglycemia during the day
-0.145 utility of
Interval -0.224 to -0.065
0.104 utility of
Interval 0.016 to 0.193
Patient Medication Preference as Estimated by a Choice Model
Hypoglycemia during day and/or night
-0.495 utility of
Interval -0.562 to -0.428
-0.429 utility of
Interval -0.51 to -0.348
Patient Medication Preference as Estimated by a Choice Model
No nausea
1.158 utility of
Interval 1.075 to 1.24
0.739 utility of
Interval 0.629 to 0.849
Patient Medication Preference as Estimated by a Choice Model
Nausea for 30 min/day
-0.262 utility of
Interval -0.345 to -0.179
0.236 utility of
Interval 0.162 to 0.31
Patient Medication Preference as Estimated by a Choice Model
Nausea for 90 min/day
-0.896 utility of
Interval -0.961 to -0.83
-0.975 utility of
Interval -1.084 to -0.866
Patient Medication Preference as Estimated by a Choice Model
1 pill/day
0.561 utility of
Interval 0.504 to 0.618
0.456 utility of
Interval 0.353 to 0.56
Patient Medication Preference as Estimated by a Choice Model
2 pills/day
0.128 utility of
Interval 0.054 to 0.202
0.348 utility of
Interval 0.23 to 0.467
Patient Medication Preference as Estimated by a Choice Model
$30 out-of-pocket cost
-0.051 utility of
Interval -0.134 to 0.032
0.077 utility of
Interval -0.116 to 0.271
Patient Medication Preference as Estimated by a Choice Model
$50 out-of-pocket cost
-0.850 utility of
Interval -0.919 to -0.78
-0.628 utility of
Interval -0.791 to -0.464

PRIMARY outcome

Timeframe: One-time survey

Population: Respondents who completed the survey.

Relative attribute importance (RAI) for each attribute in each arm measures the overall importance of that attribute. It is estimated by subtracting the lowest parameter estimate from the highest parameter estimate within each attribute. The RAI was then re-scaled on a 0 to 10 scale with 0 demonstrating no importance and 10 reflecting the most important attribute in each arm.

Outcome measures

Outcome measures
Measure
Best-Worst Scaling (Case 2)
n=551 Participants
Preference measured by best-worst scaling (case 2) survey method Best-Worst Scaling (Case 2): Respondents receive questions asking them to choose the best and worst features of a hypothetical medication.
Discrete Choice Experiment
n=552 Participants
Preference measured by discrete choice experiment Discrete Choice Experiment: Respondents receive questions asking them to choose the medication they prefer between a pair of hypothetical medications.
Weight Respondents Assign to Medication Attribute (Relative Attribute Importance) Assessed by a Choice Model
HbA1c decrease
10 units on a scale
Interval 9.54 to 10.46
5.745 units on a scale
Interval 5.182 to 6.308
Weight Respondents Assign to Medication Attribute (Relative Attribute Importance) Assessed by a Choice Model
Duration of stable HbA1c
7.496 units on a scale
Interval 7.159 to 7.833
5.040 units on a scale
Interval 4.453 to 5.626
Weight Respondents Assign to Medication Attribute (Relative Attribute Importance) Assessed by a Choice Model
Frequency of hypoglycemia
5.043 units on a scale
Interval 4.689 to 5.398
4.395 units on a scale
Interval 3.878 to 4.912
Weight Respondents Assign to Medication Attribute (Relative Attribute Importance) Assessed by a Choice Model
Duration of nausea
9.125 units on a scale
Interval 8.755 to 9.494
10 units on a scale
Interval 9.567 to 10.433
Weight Respondents Assign to Medication Attribute (Relative Attribute Importance) Assessed by a Choice Model
Treatment burden
5.553 units on a scale
Interval 5.225 to 5.88
7.358 units on a scale
Interval 6.668 to 8.048
Weight Respondents Assign to Medication Attribute (Relative Attribute Importance) Assessed by a Choice Model
Out-of-pocket cost
7.777 units on a scale
Interval 7.406 to 8.147
6.873 units on a scale
Interval 5.745 to 8.001

SECONDARY outcome

Timeframe: One-time survey

Population: Respondents who completed the survey.

Questions that asked the respondents to evaluate if the Best-Worst Scaling (BWS) or Discrete Choice Experiment (DCE tasks were easy to understand and answer.

Outcome measures

Outcome measures
Measure
Best-Worst Scaling (Case 2)
n=551 Participants
Preference measured by best-worst scaling (case 2) survey method Best-Worst Scaling (Case 2): Respondents receive questions asking them to choose the best and worst features of a hypothetical medication.
Discrete Choice Experiment
n=552 Participants
Preference measured by discrete choice experiment Discrete Choice Experiment: Respondents receive questions asking them to choose the medication they prefer between a pair of hypothetical medications.
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to understand the questions · Strongly disagree
20 Participants
13 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to understand the questions · Disagree
49 Participants
36 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to understand the questions · Neither agree nor disagree
123 Participants
111 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to understand the questions · Agree
248 Participants
292 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to understand the questions · Strongly agree
105 Participants
99 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to understand the questions · Refused
6 Participants
1 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to answer all the questions · Strongly disagree
18 Participants
15 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to answer all the questions · Disagree
73 Participants
61 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to answer all the questions · Neither agree nor disagree
133 Participants
123 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to answer all the questions · Agree
225 Participants
262 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to answer all the questions · Strongly agree
94 Participants
89 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
I found it easy to answer all the questions · Refused
8 Participants
2 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
My answers are consistent with my preferences · Strongly disagree
8 Participants
12 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
My answers are consistent with my preferences · Disagree
9 Participants
13 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
My answers are consistent with my preferences · Neither agree nor disagree
82 Participants
83 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
My answers are consistent with my preferences · Agree
314 Participants
318 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
My answers are consistent with my preferences · Strongly agree
132 Participants
126 Participants
Self-reported Difficulty in Understanding and Answering the Survey Questions
My answers are consistent with my preferences · Refused
6 Participants
0 Participants

Adverse Events

Best-Worst Scaling (Case 2)

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Discrete Choice Experiment

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

John FP Bridges

Johns Hopkins Bloomberg School of Public Health

Phone: 614-685-2543

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place