Martinez 2008.
| Methods | Design: cluster randomized controlled trial Theoretical framework: unstated Number of intervention groups: 1 Number of control groups: 1 Follow‐up: immediately post‐intervention | |
| Participants | N (intervention): 465
N (control): 579 Age (mean): 9.4 years Sex: male and female Ethnicity: : White |
|
| Interventions | Country: Spain Setting: school, urban and rural Provider: sports instructors, classroom teachers Duration: 9 months Intervention: the intervention group received: 1) the standard, compulsory physical education curriculum (3 hours per week of low‐to‐moderate intensity activity); 2) recreational, noncompetitive, after school physical activity program (3 x 90‐min sessions per week, for 24 weeks) Control: the control group received the standard, compulsory physical education curriculum: 3 hours per week of physical activity at low‐to‐moderate intensity | |
| Outcomes | Mean systolic blood pressure (mmHg) Mean diastolic blood pressure (mmHg) Mean blood cholesterol level (mg/dL) BMI (kg/m2) |
|
| Notes | ||
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | Comment: randomization took place using computer generated random numbers |
| Allocation concealment (selection bias) | Low risk | Comment: criterion not applicable because all participants were allocated at 1 point in time following recruitment, so at time of recruitment allocation was not known |
| Blinding (performance bias and detection bias) All outcomes | High risk | Quote: "two certified, trained nurses, who were unblinded to school allocation made the anthropometric and blood pressure measurements. The laboratory analysts who determined blood lipids were blinded to school allocation" (Martinez 2008, p14) Comment: only partial blinding implemented |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | Quote: "analyses were performed according to the intention‐to‐treat, with children analyzed in their original randomized allocation, regardless of the number of scheduled physical activity sessions attended" (Martinez 2008, p15) |
| Selective reporting (reporting bias) | Low risk | Comment: all outcomes identified a priori were reported on |
| Confounders controlled? | High risk | Comment: not all relevant confounders accounted for |
| Data collection methods valid and reliable? | Low risk | Comment: data collection methods were shown to be valid and reliable |