Motivations for (non)participation in population-based health studies among the elderly – comparison of participants and nonparticipants of a prospective study on influenza vaccination

Table 2 Effect of motivations to participate in health research on nonparticipation in the influenza vaccination study among elderly individuals (results of multivariable logistic regression analyses)

	Total sample^a			Subsample^{a b}
Items	n	AOR (95% CI)^c	p value	n	AOR (95% CI)^c	p value
The study should contain few medical interventions such as taking of blood samples.
important	183	3.01 (1.71–5.31)	<0.0001	108	3.53 (1.71–7.26)	0.001
so-so	127	0.99 (0.57–1.73)	0.98	93	1.29 (0.62–2.70)	0.50
not important	141	Ref.		99	Ref.
The study should not take up too much of my time.
important	175	2.19 (1.27–3.78)	0.005	103	2.77 (1.34–5.70)	0.006
so-so	143	1.27 (0.74–2.18)	0.39	105	1.62 (0.78–3.37)	0.20
not important	133	Ref.		92	Ref.
I receive information about my health.
important	368	Ref.		241	Ref.
so-so	56	2.50 (1.20–5.20)	0.01	39	2.58 (1.08–6.15)	0.03
not important	27	3.32 (1.12–9.81)	0.03	20	3.44 (1.01–11.77)	0.049
The study is reviewed and approved by the data security authorities.
important	324	Ref.		210	Ref.
so-so	42	2.45 (1.08–5.55)	0.03	29	3.08 (1.18–8.05)	0.02
not important	85	1.54 (0.84–2.82)	0.10	61	2.14 (1.02–4.52)	0.045
I make a contribution to society by participating in the study.
important	347	Ref.		223	Ref.
so-so	79	2.43 (1.29–4.59)	0.006	57	3.90 (1.89–8.03)	<0.0001
not important	25	2.54 (0.86–7.49)	0.09	20	4.95 (1.55–15.77)	0.007
Sex
Female	205	1.87 (1.20–2.91)	0.006	122	1.82 (1.02–3.22)	0.04
Male	246	Ref.		178	Ref.
Diabetes mellitus
Yes	59	1.82 (0.90–3.66)	0.10	42	2.27 (1.03–4.99)	0.04
No	392	Ref.		258	Ref.
Self-perceived health status
Poor/fair	83	3.53 (1.54–8.09)	0.003	62	4.00 (1.42–11.30)	0.009
Good	310	2.07 (1.19–3.59)	0.01	202	2.30 (1.12–4.73)	0.02
Very good/excellent	58	Ref.		36	Ref.

AOR adjusted odds ratio, CI confidence intervals
^aBackward elimination procedure based on the Wald test was applied to create the final model
^bThe nonparticipants whose main reason for nonparticipating in the influenza vaccination study was having been already vaccinated against influenza were excluded (see sensitivity analysis in the Methods section)
^cAdjusted for all other variables in the table

ISSN: 1471-2288