A qualitative study examining the validity and comprehensibility of physical activity items: developed and tested in children with juvenile idiopathic arthritis

BACKGROUND: Not all physical activity (PA) questionnaires (PAQ) gather information regarding PA intensity, duration, and modes and only a few were developed specifically for children. We assessed children’s comprehensibility of items derived from two published PAQs used in children along with three items designed to ascertain PA intensity in order to assess comprehensibility of items and identify response errors. We modified items to create a new PAQ for children (ASCeND). We hypothesized that children would have comprehension difficulties with some original PAQ items and that ASCeND would be easier to comprehend, and would improve recall and reporting of PA. METHODS: For this qualitative study, we recruited 30 Swedish children [ages 10–16 years; mean age = 13.0 (SD = 1.8)]; median disease activity score = 4.5 (IQR 2.2–9.0); median disease duration = 5.0 (IQR 2.6–10.8) with juvenile idiopathic arthritis (JIA) from a children’s hospital-based rheumatology clinic. We conducted cognitive interviews to identify children’s comprehension of PAQ items. Interviews were audiotaped, transcribed, and independently analyzed. In phase one, 10 children were interviewed and items modified based on feedback. In phase two, an additional 20 children were interviewed to gather more feedback and further refine the modified items, to create the ASCeND. RESULTS: The median interview time was 41 min (IQR 36–56). In phase one, 219 comments were generated regarding directions for recording PA duration, and transportation use, walking, dancing, weight-bearing exercise and cardio fitness. Based on feedback we modified the survey layout, clarified directions and collapsed or defined items to reduce redundancy. In phase two, 95 comments were generated. Most comments related to aerobic fitness and strenuous PA. Children had difficulty recalling total walking and other activities per day. Children used the weather on a particular day, sports practice, or gym schedules to recall time performing activities. The most comments regarding comprehension were generated about the 3-item PA intensity survey, suggesting children had problems responding to intensity items. CONCLUSIONS: The newer layout facilitated recall of directions or efficiency in answering items. The 3-item intensity survey was difficult to answer. Sports-specific items helped children more accurately recall the amount of daily PA. The ASCeND appeared to be easy to answer and to comprehend. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12969-019-0317-6) contains supplementary material, which is available to authorized users.