Table 1

Quality criteria and overall positive scores on each item

Criteria*Studies with positive score (%)
Study attrition and follow-up duration
AParticipation rate at baseline was at least 80%13
BResponse at first follow-up was at least 80%, or non selective non-response during first follow- up measurement was determined42
CFollow-up was at least one year77
Assessment of determinants
DDeterminants of physical activity or sedentary behaviour were measured with a reliable tool29§
EDeterminants of physical activity or sedentary behaviour were measured with a valid tool28§
Assessment of outcome measure
FPhysical activity or sedentary behaviour was measured with a reliable tool**23
GPhysical activity or sedentary behaviour was measured with a valid tool††16
Data analyses
HResults were presented as point estimates and measures of variability (SD, CI or standard error)45
IStatistical analyses included possible confounders87
JThe number of cases was at least 10 times the number of independent variables100
• * Rating of criteria: +=yes; −=no;?=unknown.

• + is given only if attrition analyses were performed and results showed no significant differences between dropouts and follow-up participants.

• + is given only if measures of determinants showed test-retest correlations of ≥0.80 or κ/ICC ≥0.70. For biological/demographic variables, a + was given only if a standardised protocol was followed, and trained researchers assessed the determinants.

• § Expressed as the number of cases in which the measurement of determinants were scored +, divided by the total number of determinants measured in all studies.

• + is given only if measures of determinants showed correlations of ≥0.80 or κ/ICC ≥0.70 with other similar constructs. For behavioural variables (ie, past physical activity and past sedentary behaviour), a + was given only if variables were assessed with an objective measurement instrument (ie, accelerometer/pedometer). For biological/demographic variables, a + was given only if a standardised protocol was followed, and trained researchers assessed the determinants.

• ** + is given only if physical activity or sedentary behaviour was assessed with an objective measurement instrument (accelerometer/pedometer), or questionnaire with test-retest correlations of ≥0.80 or κ/ICC ≥0.70.

• †† + is given only if physical activity or sedentary behaviour was assessed with an objective measurement instrument (accelerometer/pedometer), or validated questionnaire with correlations of ≥0.80 or κ/ICC ≥0.70, or a combination of accelerometer/pedometer and questionnaire.