Nonpharmacological Treatment for Supporting Social Participation of Adults with Depression

Table 2

Strength of evidence (level of certainty).

Strength	Description
Strong	(i) Two or more level I studies; (ii) The available evidence usually includes consistent results from well-designed, well-conducted studies. The findings are strong, and they are unlikely to be strongly called into question by the results of future studies
Moderate	(i) At least one level I high-quality study or multiple moderate-quality studies (level II, level III, etc.); (ii) The available evidence is sufficient to determine the effects on health outcomes, but confidence in the estimate is constrained by such factors as; (i) the number, size, or quality of individual studies; (ii) inconsistency of findings across individual studies; As more information (other research findings) becomes available, the magnitude or direction of the observed effect could change, and this change may be large enough to alter the conclusion related to the usefulness of the intervention
Low	(i) Small number of low-level studies, flaws in the studies, etc.; (ii) The available evidence is insufficient to assess effects on health and other outcomes of relevance to occupational therapy. Evidence is insufficient because of the following: (i) The limited number or size of studies; (ii) Important flaws in study design or methods; (iii) Inconsistency of findings across individual studies; (iv) Lack of information on important health outcomes; More information may allow estimation of effects on health and other outcomes of relevance to occupational therapy

Reference: the U.S. Preventive Services Task Force [24].