The Polish CAPAS-Q demonstrates good to excellent test-retest reliability and moderate criterion validity for sedentary behavior, but weak validity for quantifying physical activity volume, particularly in younger children and adolescent girls.
Key Findings
Results
Internal consistency of the Polish CAPAS-Q was acceptable overall, with Cronbach's alpha of 0.674 for physical activity and 0.754 for sedentary behavior.
Study involved 206 participants (114 girls, 92 boys) aged 8 to 17 years.
Cronbach's alpha for the PA dimension was 0.674, falling at the lower boundary of acceptable consistency.
Cronbach's alpha for the SB dimension was 0.754, indicating acceptable internal consistency.
Internal consistency varied across subgroups, being lower in younger children.
Results
Test-retest reliability of the Polish CAPAS-Q was good to excellent across subscales.
Participants completed the CAPAS-Q twice with a 7-day interval between administrations.
Intraclass correlation coefficients (ICC) for subscales ranged from 0.7429 to 0.9375.
ICC values in the range of 0.74 to 0.94 are classified as good to excellent reliability.
Test-retest reliability was assessed using the intraclass correlation coefficient (ICC).
Results
The sedentary behavior dimension of the CAPAS-Q showed moderate criterion validity when compared against accelerometer-derived measures.
Objective PA and SB data were collected using ActiGraph wGT3X-BT accelerometers concurrently with questionnaire completion.
The SB dimension showed a moderate negative correlation with accelerometer-derived total PA (rs = -0.41).
The SB dimension showed a moderate positive correlation with accelerometer-derived sedentary time (rs = 0.41).
Criterion validity was assessed using Spearman's rank correlation (rs).
Results
The physical activity subscales of the CAPAS-Q showed generally weak criterion validity against accelerometer data.
PA subscale correlations with accelerometer-derived measures were generally smaller than those for the SB dimension.
The highest association found for PA subscales was between sports/leisure PA and moderate to vigorous PA (rs = 0.27).
A correlation of rs = 0.27 is considered weak, indicating limited ability of the PA subscales to quantify PA volume.
Lower PA validity was specifically noted in younger children and adolescent girls.
Results
Psychometric properties of the CAPAS-Q varied by subgroup, with younger children and adolescent girls showing lower validity for the PA dimension.
The study sample included participants aged 8 to 17 years, allowing comparison across age groups.
Younger children demonstrated lower internal consistency and PA criterion validity compared to older participants.
Adolescent girls showed lower PA validity compared to other subgroups.
The authors recommend caution when interpreting PA levels derived from the CAPAS-Q in younger children and adolescent girls.
Conclusions
The Polish CAPAS-Q is recommended as a cost-effective instrument for contextual screening in epidemiological studies rather than precise quantification of physical activity volume.
The questionnaire is described as providing 'valuable contextual and qualitative data' despite weak PA validity.
Authors recommend it as a 'cost-effective instrument for contextual screening in epidemiological studies.'
Caution is advised when interpreting PA levels in younger children and adolescent girls.
The tool's moderate SB validity supports its use for identifying sedentary behavior patterns in population-level research.
What This Means
This research suggests that a Polish-language questionnaire designed to measure physical activity and sitting/sedentary time in children and adolescents — called the CAPAS-Q — performs reliably when the same children answer it twice over a one-week period, with scores remaining consistent across both attempts. The study tested 206 Polish children and teenagers aged 8 to 17 by having them complete the questionnaire twice and also wear an activity-tracking device (accelerometer) to objectively measure their movement. When comparing questionnaire responses to the accelerometer data, the tool was moderately accurate at capturing how much time children spent being sedentary, but was only weakly accurate at measuring actual physical activity levels, especially in younger children and girls.
This research suggests that the CAPAS-Q is a useful and low-cost tool for large-scale studies that want to understand the types and contexts of physical activity and sedentary behavior in youth — for example, whether kids are active at school versus in leisure time — rather than for precisely measuring how much physical activity they get. However, researchers and health professionals should interpret physical activity scores from this questionnaire cautiously, particularly for younger children and adolescent girls, where the tool performed less accurately.
The broader importance of this work lies in the ongoing global public health concern about insufficient physical activity and excessive sedentary time among young people. Having validated, easy-to-use tools in multiple languages helps researchers track these behaviors across different populations and design better interventions, even when expensive equipment like accelerometers is not practical for large studies.
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Baran R, Baran J, Leszczak J, Fillon A, Thivel D, Wyszyńska J. (2026). Validation of the Children and Adolescents Physical Activity and Sedentary Questionnaire (CAPAS-Q) in Polish Children and Adolescents.. Medical science monitor : international medical journal of experimental and clinical research. https://doi.org/10.12659/MSM.953567