Table 1.
Quality Score Assessment Criteria for the Included Studies
| Score | Gkrania‐Klotsas et al, 201218 | Haider et al, 200212 | Fagerberg et al, 199916 | Simanek et al, 201119 | |
|---|---|---|---|---|---|
| Selection | |||||
| (1) Representativeness of the exposed cohort | |||||
| (a) Truly representative of the individuals exposed to CMV infection in the community | 2 | 2 | 2 | 2 | 2 |
| (b) Somewhat representative of the individuals exposed to CMV infection in the community | 1 | … | … | … | … |
| (c) Selected group of users (eg, nurses, volunteers) | 0 | … | … | … | … |
| (d) No description of the derivation of the cohort | 0 | … | … | … | … |
| (2) Selection of the nonexposed cohort | |||||
| (a) Drawn from the same community as the exposed cohort | 2 | … | … | 2 | 2 |
| (b) Drawn from a different source | 1 | … | … | … | … |
| (c) No description of the derivation of the nonexposed cohort | 0 | … | … | … | … |
| (3) Ascertainment of exposure | |||||
| (a) Laboratory test | 2 | 2 | 2 | 2 | 2 |
| (b) Medical record | 1 | … | … | … | … |
| (c) Written self report | 0 | … | … | … | … |
| (4) Demonstration that outcome of interest was not present at start of study | |||||
| (a) Yes | 1 | 1 | 1 | 1 | |
| (b) No | 0 | … | … | 0 | … |
| Comparability | |||||
| (1) Comparability of cohorts on the basis of the design or analysis | |||||
| (a) Study controls for age and any additional factor | 2 | 2 | 2 | 2 | 2 |
| (b) Study controls for any confounding factor | 1 | … | … | … | … |
| (c) No adjustment | 0 | … | … | … | … |
| Outcome | |||||
| (1) Assessment of outcome | |||||
| (a) Referencing to secure records | 3 | … | 3 | 3 | … |
| (b) Record linkage | 2 | 2 | … | … | 2 |
| (c) Self report | 1 | … | … | … | … |
| (d) No description | 0 | … | … | … | … |
| (2) Was follow‐up long enough for outcomes to occur? | |||||
| (a) Yes (≥4 y) | 1 | 1 | 1 | 1 | 1 |
| (b) No | 0 | … | … | … | … |
| Total score | 13 | 12 | 13 | 12 | 12 |
| Quality levela | High | High | Medium | High | |
| Score | Roberts et al, 201014 | Spyridopoulos et al, 201620 | Corrado et al, 200621 | Smieja et al, 200313 | Elkind et al, 201010 | |
|---|---|---|---|---|---|---|
| Selection | ||||||
| (1) Representativeness of the exposed cohort | ||||||
| (a) Truly representative of the individuals exposed to CMV infection in the community | 2 | 2 | 2 | 2 | 2 | 2 |
| (b) Somewhat representative of the individuals exposed to CMV infection in the community | 1 | … | … | … | … | … |
| (c) Selected group of users (eg, nurses, volunteers) | 0 | … | … | … | … | … |
| (d) No description of the derivation of the cohort | 0 | … | … | … | … | … |
| (2) Selection of the nonexposed cohort | ||||||
| (a) Drawn from the same community as the exposed cohort | 2 | 2 | 2 | 2 | 2 | 2 |
| (b) Drawn from a different source | 1 | … | … | … | … | … |
| (c) No description of the derivation of the nonexposed cohort | 0 | … | … | … | … | … |
| (3) Ascertainment of exposure | ||||||
| (a) Laboratory test | 2 | 2 | 2 | 2 | 2 | 2 |
| (b) Medical record | 1 | … | … | … | … | … |
| (c) Written self report | 0 | … | … | … | … | … |
| (4) Demonstration that outcome of interest was not present at start of study | ||||||
| (a) Yes | 1 | 1 | 1 | 1 | 1 | 1 |
| (b) No | 0 | … | … | … | … | … |
| Comparability | ||||||
| (1) Comparability of cohorts on the basis of the design or analysis | ||||||
| (a) Study controls for age and any additional factor | 2 | 2 | … | 2 | 2 | 2 |
| (b) Study controls for any confounding factor | 1 | … | 1 | … | … | … |
| (c) No adjustment | 0 | … | … | … | … | … |
| Outcome | ||||||
| (1) Assessment of outcome | ||||||
| (a) Referencing to secure records | 3 | … | 3 | 3 | … | 3 |
| (b) Record linkage | 2 | 2 | … | … | 2 | … |
| (c) Self report | 1 | … | … | … | … | … |
| (d) No description | 0 | … | … | … | … | … |
| (2) Was follow‐up long enough for outcomes to occur? | ||||||
| (a) Yes (≥4 y) | 1 | 1 | 1 | 1 | 1 | 1 |
| (b) No | 0 | … | … | … | … | … |
| Total score | 13 | 12 | 12 | 13 | 12 | 13 |
| Quality levela | High | High | High | Medium | High | |
CMV indicates cytomegalovirus.
a
Quality level was defined as low (≤7), medium (8–10), or high (≥11) according to quality score.