| Study | Reason for exclusion |
|---|---|
| Coutinho 1976 | Population: adults |
| Girschick 1999 | Allocation: not a randomised controlled trial |
| Jenkins 1976 | Population: adults |
| Johnsen 1992 | Population: adults |
| Natour 2002 | Population: adults |
| Reicher 1969 | Allocation: not a randomised controlled trial |
| Sadowska‐Wroblewska 1980 | Population: adults |
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