Table 1 Overview of responses from cognitive debriefing interviews

Interview number

1

2

3

4

5

6

7

Participant characteristics

Female, age 59 years

General population

RAPA activity level: active

RAPA Score: 6

Female, age 66 years

General population

RAPA activity level: active

RAPA Score: 6

Male, age 60 years

General population

RAPA activity level: active

RAPA Score: 7

Female, age 55 years

Orthopedic rehabilitation

RAPA activity level: active

RAPA score: 10

Male, age 65 years

Cardiac rehabilitation

RAPA activity level: active

RAPA score: 10

Male, age 69 years

Cardiac rehabilitation

RAPA activity level: under-active regular – light activities

RAPA score: 3

Male, age 66 years

Cardiac patient

RAPA activity level: active

RAPA score: 10

Time to complete the RAPA questionnaire

2 min 20 s

2 min

1 min 45 s

2 min 20 s

1 min 30 s

2 min

5 min

Design (layout, font size, spacing on the page)

Design is appropriate

Design is clear and fits well

Design is appropriate

Design is appropriate

Design is clear and it is easy to read (font size)

Design is appropriate

Appropriate

Offensive or questionable content

None, all questions are worded politely

None

None

None

None

None

None

Explanation of physical activity and intensity

Sometimes the examples may not be suitable, for example strength training as well as aerobics class can also be vigorous activities, because the content is not clearly defined

Understandable

The participant found the categories do not apply to his physical activity, because he is regularly doing hard construction work, so it was difficult for him to select the correct answer; maybe the intensity categories and example activities are not suitable for a hard-working person

Understandable, easy to read, even without glasses

Understandable, appropriate graphics

The given examples were easy to understand and graphics were helpful

Helpful to understand levels of exertion in relation to heart rate; the examples could include an image of gardening, which could be a moderate intensity activity; questions the image of an old man for ‘walking at a slow pace’

Wording of the questions

Time specifications in items 4, 5 and 6 are incomprehensible; she had to read these items repeatedly to understand their meaning

Content is meaningful but items 4 and 5 caused some confusion

Content is meaningful and easy to understand

Items 4 and 5 are difficult to grasp, but overall, the content is meaningful

Content is meaningful and easy to go through

Content for items 1–3 is meaningful and easy to understand; items 4–5 were too long and harder to understand (but not impossible); items 6–7 and the items on strength and flexibility were easy to understand

Answered items 4 and 5 incorrectly upon first completion, had to read repeatedly to understand the meaning; suggests to split items 4 and 5 into two items each, asking about each level of activity separately

Response options

Yes and no answer options are appropriate in relation to the questions

Sometimes difficult to choose between yes and no, but then considered for herself whether it is more likely to be yes or no and ticked accordingly; in general, she prefers to define answers herself

Yes and no answer options are appropriate in relation to the questions

Yes and no answer options are appropriate in relation to the questions

Yes and no answer options are appropriate in relation to the questions

Yes and no answer options are appropriate in relation to the questions

Clear, able to relate all response options to himself

Interview number

8

9

10

11

12

13

Participant characteristics

Female, age 71 years

General population

RAPA activity level: active

RAPA Score: 10

Female, 73 years

General population

RAPA activity level: active

RAPA score: 6

Male, 78 years old

Neurologic patient

RAPA activity level: under-active regular

RAPA score: 8

Male, age 56 years

Cardiac rehabilitation

RAPA activity level: active

RAPA score: 6

Male, age 56 years

Post-COVID-19 rehabilitation

RAPA activity level: active

RAPA score: 6

Male, age 73 years

Cardiac patient

RAPA activity level: under-active

RAPA score: 2

Time to complete the RAPA questionnaire

5 min 20 s

2 min 10 s

5 min 30 s

2 min 30 s

2 min 30 s

4 min 20 s

Design (layout, font size, spacing on the page)

Good font size, appropriate layout

Appropriate

Good

Good

Good

Good, font size appropriate for older people

Offensive or questionable content

None

None

None

None

None

None

Explanation of physical activity and intensity

Understandable, but also the level of exertion experienced with any of the example activities depends on the individual; yoga can be moderate exertion for some, aerobics class can be a vigorous activity for some, etc

Appropriate, understandable

Appropriate

Clear

Clear

Cutting wood, which he does regularly, is also a strenuous activity; the level of effort/intensity also depends on the individual

Wording of the questions

Items 4 and 5 are very confusing; had to read these repeatedly and did not grasp the 2 alternatives within each item

Overall clear, some items require reading twice (specifically 4 and 5)

Clear and make sense; needed to read some items twice, but able to relate to own physical activity

Somewhat confusing, needed to read repeatedly, especially those questions which include two options; but understandable after repeated reading

Initially confusing, needed to read through all questions to understand the logic; but then understandable and able to relate to own physical activity

Had to read through some questions repeatedly to be clear on differences in days/minutes between questions; overall understandable and able to relate to own physical activity

Response options

Appropriate, and for those items where the question wording is clear the answer options make sense

Make sense, although could also offer a 5-point rating

Make sense, but could also be formulated as 5-point rating

Clear and make sense

Appropriate

Appropriate