Study ID | Internal validitya | External validityb | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Randomization | Allocation concealment | Blinding of outcome Measurement | Incomplete outcome data | Precision of effect estimates | Study design and Setting | Intervention and Control - assessment of performance bias | Outcome measurements, results and evaluation- assessment of detection bias | Indirectness: study population – assessment of selection bias | Directness of body of evidence | Rating of external validity | |
Clemson 2016 [28] | Low risk | Low risk | Low risk | High risk | + | + | (+) | (+) | (+) | (+) | (+) |
López Cabezas 2006 [29] | Low risk | Low risk | High risk | Low risk | (+) | + | (+) | (+) | (+) | (+) | (+) |
Rich 1995 [30] | Low risk | Low risk | Low risk | Low risk | (+) | + | (+) | (+) | (+) | (+) | (+) |