Table 4 Certainty of evidence for the protective factors associated with mitigating adverse mental health outcomes on health and care staff during the COVID-19 pandemic
| No of studies | Design | Risk of bias | Additional considerations | Certainty (overall score)a |
|---|---|---|---|---|
| Factor: Support (Community, social, team, government) [24, 37, 44, 46] | ||||
| 4 | 2 | 2 | No serious inconsistencies. |
 High
|
| Factor: Adequate personal protective equipment (PPE) [24, 46] | ||||
| 2 | 2 | 0 | Few studies assessed PPE directly as a protective factor. Many found it to be a risk factor when inadequate. |
 Low
|
| Factor: Being in a committed relationship [36] | ||||
| 1 | 2 | 0 | Only one study assessed this factor. |
 Very low
|
| Factor: Prior outbreak experience/COVID-19 Knowledge [22, 24, 46, 61] | ||||
| 4 | 2 | 1 | No serious inconsistencies, but the data also included one low quality uncontrolled pre and post exposure study, as well as a qualitative study. |
 Moderate
|
| Factor: Resilience [36, 44, 61] | ||||
| 3 | 2 | 1 | Resilience was empirically measured with validated scores |
 High
|
| Factor: Altruistic acts [37] | ||||
| 1 | 2 | 1 | Only one qualitative study assessed this factor. |
 Low
|
| Factor: Personal growth [37] | ||||
| 1 | 2 | 1 | Only one qualitative study assessed this factor. |
 Low
|
| Factor: Gratitude, Positive self-attitude [24, 37] | ||||
| 2 | 2 | 1 | This factor was not empirically measured. |
 Low
|
| Factor: Sense of purpose [37] | ||||
| 1 | 2 | 1 | Only one qualitative study assessed this factor. |
 Low
|
| Factor: Safety of family [24] | ||||
| 1 | 2 | 0 | Only one study assessed this factor. |
 Very low
|
- a4
High = This research provides a very good indication of the likely effect. The likelihood that the effect will be substantially different** is low - 3
Moderate = This research provides a good indication of the likely effect. The likelihood that the effect will be substantially different** is moderate - 2
Low = This research provides some indication of the likely effect. However, the likelihood that it will be substantially different** is high - 1
Very low = This research does not provide a reliable indication of the likely effect. The likelihood that the effect will be substantially different** is very high - ** Substantially different = a large enough difference that it might affect a decision
High = This research provides a very good indication of the likely effect. The likelihood that the effect will be substantially different** is low
Moderate = This research provides a good indication of the likely effect. The likelihood that the effect will be substantially different** is moderate
Low = This research provides some indication of the likely effect. However, the likelihood that it will be substantially different** is high
Very low = This research does not provide a reliable indication of the likely effect. The likelihood that the effect will be substantially different** is very high