Table 1.
CASP quality ratings (N = 20)
| References | Barker et al. [64] |
Brennan et al. [49] | Edwards and Hans [43] | Eichler et al. [65] | Gjerde et al. [61] | Hannington et al. [44] | Hay et al. [51] | Hay et al. [48] | Hay et al. [47] | Korhonen et al. [70] | Korhonen et al. [69] | Lahti et al. [66] | Leis et al. [71] | Luoma et al. [67] | O’connor et al. [62] | O’Donnell et al. [72] | Raskin et al. [60] | Soe et al. [63] | van de Waerden et al. [68] | Woolhouse et al. [9] |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1. Did the study address a clearly focused issue? In terms of…a | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 |
| Is the population studied clear?b | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y |
| Are the factors studied clear?b | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y |
| Are the outcomes clear?b | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y |
| 2. Was the cohort recruited in an acceptable way? (selection bias)a | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 |
| Was the cohort representative of a defined population?b | P | P | N | N | P | P | Y | Y | Y | P | P | P | P | P | P | Y | N | P | P | P |
| Was everybody included who should have been included?b | P | N | P | P | N | P | P | P | P | P | P | P | P | P | P | P | N | N | N | N |
| 3. Was the exposure accurately measured to minimise bias?a | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Did they use objective measurements?b | N | N | N | N | N | N | P | P | P | P | P | P | P | P | N | P | N | N | N | N |
| Do the measurements truly reflect what you want them to?b | Y | P | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y |
| 4. Was the outcome accurately measured to minimise bias?a | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 2 | 2 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Did they use objective measurements?b | P | P | P | P | P | P | Y | Y | Y | P | P | P | P | P | N | P | N | N | N | N |
| Do they measures truly reflect what you want them tob | Y | P | Y | N | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | P | Y | Y | Y |
| Was there blinding to exposure?b | N | N | N | N | N | N | P | Y | Y | P | P | P | P | P | ? | P | N | N | P | P |
| 5. Have the authors identified all important confounding factors?a | 2 | 2 | 1 | 0 | 2 | 2 | 2 | 2 | 2 | 0 | 0 | 2 | 2 | 1 | 1 | 2 | 1 | 2 | 2 | 2 |
| Have they taken into account the confounding factors in design/analysis?b | Y | Y | P | P | Y | Y | Y | Y | Y | N | N | Y | Y | P | P | Y | P | Y | Y | Y |
| 6. Was the follow up of subjects complete enough?a | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 |
| Was the follow up of subjects long enough?b | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y |
| 7. What are the results of the study? Are they reported clearly?a | 2 | 2 | 1 | 1 | 2 | 2 | 2 | 2 | 2 | 1 | 2 | 2 | 2 | 2 | 1 | 1 | 1 | 2 | 2 | 2 |
| Have they reported the rate or the proportion between exposedb | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | N | Y | Y | Y |
| 8. How precise are the results? | 1 | 2 | 1 | 1 | 2 | 2 | 1 | 1 | 2 | 2 | 2 | 2 | 1 | 2 | 2 | 1 | 1 | 1 | 2 | 2 |
| Were confidence intervals given?b | N | Y | N | Y | Y | Y | N | N | Y | Y | Y | Y | N | Y | Y | N | N | N | Y | Y |
| 9. Do you believe the results?a | 2 | 1 | 2 | 1 | 2 | 2 | 2 | 2 | 2 | 1 | 1 | 2 | 2 | 2 | 2 | 2 | 1 | 1 | 2 | 2 |
| Could it be due to bias, chance or confounding?b | N | P | N | P | N | N | N | N | N | P | P | N | N | N | P | N | N | N | N | N |
| Are the design/methods of this study flawed to make the results unreliable?b | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N |
| 10. Can the results be applied to the local population?a | 2 | 0 | 0 | 0 | 1 | 2 | 2 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 |
| Was the cohort the appropriate method?b | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y |
| 11. Do the results of this study fit with other available evidence?a | 2 | 1 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 1 | 0 | 2 | 1 |
| 12. Implications of this study for practice? Are they justified?a | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Overall Scorea | 19 | 14 | 14 | 12 | 18 | 20 | 19 | 19 | 20 | 15 | 16 | 19 | 18 | 18 | 17 | 17 | 12 | 13 | 19 | 18 |
| Qualitative Descriptor (0 unacceptable; + acceptable; ++ High Quality)a | ++ | + | + | + | ++ | ++ | ++ | ++ | ++ | + | + | ++ | ++ | ++ | + | + | + | + | ++ | ++ |
aThe main questions are the 1–12 (score 0 = criterion not met, 1 = mixed evidence, 2 = criterion met)
bThe questions prompt to the main questions to aid scoring (Y = yes; N = no; P = partial