Table 1 Study design and methodological issues
Study/country of origin | Study design: Com.obs Pros/long | Subject Select-ion | Control selection: matched/NS | Justification. Sample size: Y/NS | Elect. position reprod: Y/N | Reliability assessed Y/N | Tester blind to group alloc: Y/NS | Sufficient results in text: Y/N |
|---|---|---|---|---|---|---|---|---|
Boling et al [15] USA | Com.obs | Conv | NS | NS | Y | Y | NS | Y |
Brindle et al [21] USA | Com.obs | Conv | Matched for age | NS | N | N | NS | Y |
Cowan et al [5] Australia | Com.obs | Conv | NS | NS | Y | Y | NS | N |
Cowan et al [16] Australia | Com.obs | Conv | NS | From prev. study | Y | Y | NS | N |
Cowan et al [20] Australia | Com.obs | Conv | Matched for gender | NS | Y | Y | NS | N |
Crossley et al [14] Australia | Com.obs | Conv | NS | NS | N | Y | NS | Y |
Earl et al [17] USA | Com.obs | Conv | Matched on no. of factors | NS | Y | Y | NS | N |
Karst and Willett [30] USA | Com.obs | Conv | NS | NS | N | Y | NS | Y |
McClinton et al [22] USA | Com.obs | Conv | NS | NS | Y | Y | NS | Y |
Morrish & Woled ge [46] UK | Com.obs | Conv | NS | NS | N | N | NS | N |
Owings et al [19] USA | Com.obs | Conv | NS | NS | N | N | NS | Y |
Witvrouw et al [18] Belgium | Com.obs | Conv | NS | NS | Y | Y | NS | Y |
Witvrouw et al [13] Belgium | Pros. long. | Conv | NA | Not specifically for timing | Y | Y | NS | Y |
Voight & Wieder [6] USA | Com.obs | Conv | NS | NS | N | N | NS | N |