Table 3 Criteria for coding summary results [adapted from Wang and Wen [40]]
Type of result | Number of studies and relative agreement | Code |
|---|---|---|
Not able to get a summary result | 0–3 studies | N/A |
Convincing positive relationship | ≥ 4 studies, positive relationship found in ≥ 60% of studies and negative relationship in < 25% of studies | + + |
Possible positive relationship | ≥ 4 studies, positive relationship found in 41–60% of studies and negative relationship in < 25% of studies | + |
Convincingly not related | ≥ 4 studies, no significant relationship found in ≥ 60% of studies and any other direction in < 40% of studies | 0 0 |
Possible negative relationship | ≥ 4 studies, negative relationship found in 41–60% of studies and positive relationship in < 25% of studies | - |
Convincing negative relationship | ≥ 4 studies, negative relationship found in ≥ 60% of studies and positive relationship in < 25% of studies | - - |
Inconclusive | ≥ 4 studies, no consistent associations | ? |