Willingness to participate in a lifestyle intervention program of patients with type 2 diabetes mellitus: a conjoint analysis

Figures & data

Table 1 Attributes and levels

Attribute	Levels
Time spent on the program	2.5 hours per week 4 hours per week
Arrangement physical activity lessons	Individually with men and women With people of the same gender
Group activity	Only with people without diabetes Only with other diabetes patients
Sports activity	Walking/cycling Fitness (treadmill, rowing machine, bicycle)
Counseling	None Physical therapist/sports teacher
Money	Copayment = €500 per year Copayment = €327.50 per year Copayment = €155 per year Copayment = €0 per year Bonus = €0 per year Bonus = €155 per year Bonus = €327.5 per year Bonus = €500 per year

* Notes: Half of the research population received a conjoint questionnaire in which they had to pay for participating in the hypothetical lifestyle intervention. The other half received a questionnaire in which they received money for participation.

Table 2 Results of regression models based on the attributes of participation in the hypothetical lifestyle interventions (N = 46; N observations = 174)

Attributes	Logistic regression model				Linear probability model
	B	Odds ratio	95% CI	P value	B	95% CI	P value
Time spent on the program (reference category = 2.5 hours)
4 hours	−0.067	0.935	0.448 to 1.953	0.863	−0.018	−0.162 to 0.126	0.803
Arrangement of physical activity lessons (reference category = with men and women)
With people of the same gender	0.577	1.780	0.729 to 4.347	0.243	0.098	−0.072 to 0.269	0.249
Individually	0.405	1.500	0.622 to 3.619	0.402	0.066	−0.102 to 0.235	0.432
Group activity (reference category = only with people without diabetes)
Only with other diabetes patients	0.490	1.633	0.786 to 3.392	0.168	0.088	−0.041 to 0.218	0.176
Sports activity (reference category = walking/cycling)
Fitness (treadmill, rowing machine, bicycle)	0.467	1.595	0.771 to 3.296	0.206	0.076	−0.058 to 0.209	0.258
Counseling (reference category = no counseling)
Counseling from a physical therapist/sports instructor	0.281	1.325	0.631 to 2.783	0.513	0.046	−0.110 to 0.203	0.551
Money	0.006	1.006	1.002 to 1.011	0.025	0.0008	0.000 to 0.001	0.014
Copayment = €500 per year
Copayment = €327.50 per year
Copayment = €155 per year
€0 per year
Bonus = €155 per year
Bonus = €327.50 per year
Bonus = €500 per year
Receiving	−0.429	0.651	0.220 to 1.930	0.579	−0.051	−0.370 to 0.266	0.744
Interaction receiving*money	−0.006	0.994	0.990 to 0.999	0.050	−0.0006	−0.002 to 0.000	0.126
Intercept	−1.258	0.284	0.098 to 0.827	0.045	0.226	−0.017 to 0.468	0.067

Abbreviations: CI, confidence interval; €, euro.

Table 3a Results of regression models based on the attributes of participation in the hypothetical lifestyle interventions: adjusted for gender, age, and BMI (N = 37; N observations = 158)

Attributes	Logistic regression model				Linear probability model
	B	Odds ratio	95% CI	P value	B	95% CI	P value
Time spent on the program (reference category = 2.5 hours)
4 hours	−0.441	0.643	0.324 to 1.279	0.208	−0.092	−0.214 to 0.030	0.134
Arrangement of physical activity lessons (reference category = with men and women)
With people of the same gender	0.408	1.503	0.570 to 3.975	0.409	0.069	−0.093 to 0.232	0.389
Individually	−0.009	0.991	0.317 to 3.099	0.987	0.011	−0.177 to 0.199	0.908
Group activity (reference category = only with people without diabetes)
Only with other diabetes patients	0.735	2.085	0.975 to 4.459	0.058	0.134	0.008 to 0.261	0.038
Sports activity (reference category = walking/cycling)
Fitness (treadmill, rowing machine, bicycle)	0.577	1.780	0.751 to 4.225	0.191	0.095	−0.053 to 0.244	0.202
Counseling (reference category = no counseling)
Counseling from a physical therapist/sports instructor	1.01	2.746	1.094 to 6.876	0.031	0.158	0.009 to 0.307	0.038
Money	0.008	1.008	1.002 to 1.015	0.010	0.001	0.000 to 0.002	0.001
Copayment = €500 per year
Copayment = €327.50 per year
Copayment = €155 per year
€0 per year
Bonus = €155 per year
Bonus = €327.50 per year
Bonus = €500 per year
Receiving	−1.417	0.230	0.068 to 0.857	0.028	−0.243	−0.486 to −0.001	0.049
Interaction receiving*money	−0.007	0.993	0.986 to 0.999	0.030	−0.001	−0.002 to 0.000	0.061
Gender (reference category = women)	−0.262	0.770	0.331 to 1.790	0.543	−0.064	−0.208 to 0.079	0.368
Age (reference category < 75 years of age)	−1.417	0.242	0.064 to 0.918	0.037	−0.236	−0425 to −0.047	0.016
BMI (reference category < BMI 30 kg/m^2)	−0.360	0.698	0.241 to 2.014	0.506	−0.048	−0237 to 0.141	0.611
Intercept	−0.272	0.762	0.202 to 2.863	0.687	0.418	0.168 to 0.669	0.002

Abbreviations: BMI, body mass index; CI, confidence interval; €, euro.

Table 3b Results of regression models based on the attributes of participation in the hypothetical lifestyle interventions: adjusted for gender, age, BMI, and income (N = 32; N observations = 125)

Attributes	Logistic regression model				Linear probability model
	B	Odds ratio	95% CI	P value	B	95% CI	P value
Time spent on the program (reference category = 2.5 hours)
4 hours	−0.335	0.715	0.295 to 1.735	0.458	−0.084	−0.245 to 0.0770	0.295
Arrangement of physical activity lessons (reference category = with men and women)
With people of the same gender	0635	1.887	0.526 to 6.773	0.330	0.097	−0.111 to 0.305	0.349
Individually	0.444	1.559	0.430 to 5.652	0.500	0.072	−0.148 to 0.294	0.506
Group activity (reference category = only with people without diabetes)
Only with other diabetes patients	0.531	1.701	0.698 to 4.145	0.243	0.101	−0.054 to 0.257	0.193
Sports activity (reference category = walking/cycling)
Fitness (treadmill, rowing machine, bicycle)	0.731	2.077	0.742 to 5.818	0.164	0.116	−0.077 to 0.310	0.230
Counseling (reference category = no counseling)
Counseling from a physical therapist/sports instructor	0.908	2.482	0.870 to 7.078	0.089	0.152	−0.024 to 0.329	0.089
Money	0.009	1.009	1.001 to 1.016	0.021	0.001	0.000 to 0.002	0.002
Copayment = €500 per year
Copayment = €327.50 per year
Copayment = €155 per year
€0 per year
Bonus = €155 per year
Bonus = €327.50 per year
Bonus = €500 per year
Receiving	−1.711	0.181	0.044 to 0.738	0.017	−0.304	−0.577 to −0.031	0.030
Interaction receiving * money	−0.006	0.994	0.987 to 1.002	0.132	−0.001	−0.001 to 0.000	0.252
Sex (reference category = women)	−0.921	0.912	0.386 to 2.155	0.834	−0.026	−0.185 to 0.134	0.744
Age (reference category < 75 years of age	−1.058	0.347	0.082 to 1.461	0.149	−0.215	−0.477 to 0.046	0.103
BMI (reference category < BMI 30 kg/m^2)	−0.614	1.848	0.172 to 1.704	0.294	−0.099	−0.300 to 0.101	0.319
Income (reference category = low income)	0.427	1.533	0.405 to 5.789	0.529	0.071	−0.152 to 0.294	0.522
Intercept	−0.463	0.629	0.130 to 3.056	0.566	0.410	0.097 to 0.723	0.012

Abbreviations: BMI, body mass index; CI, confidence interval; €, euro.

Figure A1 Example scenario.

Note: *Results were not used in this paper.