Table 1 Overview of constructs measured by the online survey

Intention

α = .88

I would be willing to vaccinate people aged 60 years and older against infectious diseases other than influenza.

Attitude

r = .64

I think vaccination as a preventive tool is: 1 = not very useful; 7 = very useful.

Attitude additional vaccination

n.a.

Offering additional vaccination other than influenza vaccination to people aged 60 years and older is necessary.

Attitude vaccination 80+

n.a.

Offering people 80 years and older some form of vaccination is still useful.

Attitude outbreak

n.a.

Vaccinating people 60 years and older with or without co-morbidities during an outbreak of an infectious disease is always useful.

Perceived severity (per infectious disease)

n.a.

How serious do you think are the different diseases for people aged 60 years and older? Influenza/ herpes zoster/ pneumonia/ pertussis: 1 = not severe at all; 7 = very severe. These are four separate items.

Selection comorbidity over age

α = .81

Vaccinating people on the basis of co-morbidities is favored over vaccinating people on the basis of age, irrespective of the infectious disease.

Prevention

n.a.

In general, prevention of illness has the preference over cure.

Prevention mortality

n.a.

Additional vaccines should primarily be focused on the prevention of death.

Prevention morbidity

n.a.

Additional vaccines should primarily be focused on the prevention of illness

Usefulness health benefits

n.a.

In the consideration to offer vaccination, individual health benefits are more important than cost-effectiveness on the population level.

Intention (per infectious disease)

n.a.

I would recommend healthy people in their 60s to get vaccinated against pneumococcal disease/ herpes zoster/ pertussis. These are three separate items.

Intention comorbidity (per infectious disease)

n.a.

I would recommend people in their 60s who have a comorbidity to get vaccinated against pneumococcal disease/ herpes zoster/ pertussis. These are three separate items.