Cognitive and affective determinants of generic drug acceptance and use: cross-sectional and experimental findings

Figures & data

Table 1. Item wording, means (M), standard deviations (SD), and Cronbach's alpha (α) of the scales used in the questionnaire.

Scales	M	SD	α
SVM	4.58	0.97	0.55
Health is about something …
1. … that we should not sacrifice, no matter what the benefits (money or something else)	5.54	1.45
2. … which one cannot quantify with money	6.20	1.29
3. … for which I think it is right to make cost–benefit analyses. (R)	3.00	1.76
4. … for which I can be flexible if the situation demands it. (R)	2.94	1.59
5. … that involves issues or values which are inviolable	5.26	1.68
Beliefs	5.23	0.85	0.73
1. Generic drugs could help fight diseases in developing countries	5.95	1.32
2. It should always be allowed to approve generic drugs, regardless of whether the patent of the brand drug has expired or not; this would then ensure that poor people have access to these drugs	4.92	1.97
3. The introduction of generic drugs forces researchers and pharmaceutical companies to conduct research into new drugs	4.44	1.84
4. Cost savings from generic drugs help to create financial scope for expensive pharmaceutical innovations	4.20	1.93
5. Generic drugs help to enhance cost-consciousness in the health care system.	5.88	1.41
6. In the long term, generic drugs will create a two-class society. (R)	5.12	1.87
7. Producers of generic drugs profit disproportionately from the achievements of other researchers or pharmaceutical producers. (R)	3.87	1.66
8. Generic drugs are a better value than brand-name drugs^a	5.75	1.47
9. Swiss people spend too much money on prescription drugs^a	6.02	1.39
10. Swiss people should use more generic drugs^a	6.02	1.40
11. The government should create new rules to increase generic drug use in Switzerland^a	5.24	1.89
12. Healthcare insurance companies should create new rules to increase generic drug use^a	5.25	1.86
Acceptance of generic drugs	4.24	1.42	0.85
1. When I receive a new prescription from my doctor, I often ask if a cheaper generic option is available^a	4.53	2.09
2. I feel comfortable asking my doctor to substitute a generic form of a brand-name medication^a	5.01	1.96
3. At the pharmacy, I often ask if a cheaper generic option is available.^a	4.55	2.07
4. I feel comfortable asking my pharmacist to substitute a generic form of a brand-name medication^a	4.75	2.01
5. I don't mind when my pharmacist switches my prescription to a generic medication.^a	5.16	1.93
6. I often search the Internet to figure out if a drug has a generic equivalent	2.23	1.71
7. At an online pharmacy, I would specifically search for generic drugs	2.74	2.09
8. I would be willing to solely receive and use generic drugs if my health insurance contribution would be lower in return	4.81	2.18
Health status	5.68	1.08

Table 2. Knowledge scale: items, per cent correct answers and scalability coefficient of the items (H_i).

Item	True/false	Per cent correct	Hi
Generic drugs are cheaper because they are less efficacious^a	F	91	0.62
Generic drugs are used for the same illnesses^a	T	89	0.49
Generic drugs have a different box from brand drugs^a,b	T	87	–
Generic drugs are purely herbal products and refrain from chemical agents	F	86	0.52
In contrast to brand drugs, generic drugs are produced on a natural basis	F	85	0.46
Generic drugs are good for less serious diseases^a	F	85	0.50
Generic drugs are made with lower quality substances^a	F	84	0.50
Generic drugs are as effective as brand drugs^a	T	83	0.49
Generic drugs have the same effect as brand drugs^a	T	83	0.45
Treatments with generic drugs take longer^a	F	82	0.55
Generic drugs take a longer time to be efficacious^a	F	81	0.58
Oftentimes, you have to take double the amount of the active ingredient of a generic drug to have the same effect as the brand drug	F	78	0.50
Compared with brand drugs, generic drugs have been on the market a shorter period of time, so they carry more risks and side effects	F	74	0.51
Generic antibiotics are less efficacious than brand antibiotics^a	F	68	0.55
Physicians who are allowed to dispense drugs to their patients on their own account don't dispense generic drugs^b	F	67	–
The active ingredients in generic drugs have the same side effects as active ingredients in brand drugs^a	T	65	0.44
Producers of generic drugs have to incur less research expenditures for the development of their drugs^b	T	61	–
Generic drugs have a better quality control than brand drugs^a	F	55	0.45
Generic contraceptives are as safe as brand contraceptives	T	51	0.56
Generic drugs can contain different inactive ingredients than brand drugs^b	T	48	–
Generic drug producers and brand drug producers have to spend an equal amount of money for patent protection	F	39	0.45
In the Swiss health insurance system, the patient copayment amount for drugs is always the same^b	F	29	–

Figure 1. Network visualisation and affective imagery elicited by free associations to generic drugs. Nodes are sized according to the frequency with which each category was generated. Node colour shows mean rating of the category (black = positive; grey = neutral; white = negative). Tie strength denotes how often a category was mentioned in connection with another category.

Table 3. Multiple linear regression predicting acceptance of generic drugs (n = 583).

	B	SE B	β	p-Value
Constant	−0.861	0.548		0.117
Gender (male)	−0.138	0.093	−0.049	0.139
Age	0.002	0.003	0.017	0.626
Education
Low verus medium	0.103	0.195	0.036	0.599
Low versus high	0.031	0.200	0.011	0.876
Income	−0.044	0.059	−0.026	0.455
Health status	0.078	0.044	0.059	0.076
Affect	0.125	0.038	0.116	0.001
SVM	−0.093	0.048	−0.063	0.054
Knowledge	0.066	0.013	0.187	0.000
Beliefs	0.817	0.060	0.492	0.000

Table 4. Multiple logistic regression predicting generic drug choice for flu and thrombosis.

	Flu						Thrombosis
	B	Odds ratio	95% CI			p-Value	B	Odds ratio	95% CI			p-Value
Constant	−5.48	0.00				0.012	−7.27	0.00				0.000
Gender (male)	0.16	1.17	0.56	–	2.46	0.682	−0.12	0.88	0.53	−	1.46	0.630
Age	0.01	1.01	0.98	–	1.03	0.543	0.02	1.02	1.00	−	1.03	0.067
Education										−
Low versus medium	−0.19	0.83	0.19	−	3.64	0.801	0.67	1.96	0.69	−	5.56	0.207
Low versus high	0.19	1.21	0.26	−	5.71	0.813	0.29	1.33	0.46	−	3.86	0.596
Income	−0.45	0.64	0.38	−	1.06	0.080	−0.21	0.81	0.59	−	1.12	0.203
Health status	0.26	1.30	0.93	−	1.81	0.125	0.24	1.27	1.00	−	1.60	0.050
Affect	0.42	1.52	1.13	−	2.05	0.006	0.26	1.29	1.05	−	1.59	0.014
SVM	−0.29	0.75	0.50	−	1.11	0.151	−0.19	0.83	0.64	−	1.08	0.169
Knowledge	0.17	1.18	1.10	−	1.27	0.000	0.16	1.17	1.10	−	1.25	0.000
Beliefs	1.32	3.75	2.34	−	5.99	0.000	1.08	2.93	2.10	−	4.10	0.000

Shrank, W. H., Cadarette, S. M., Cox, E., Fischer, M. A., Mehta, J., Brookhart, A. M., … Choudhry, N. K. (2009). Is there a relationship between patient beliefs or communication about generic drugs and medication utilization? Medical Care, 47(3), 319–325.

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