Mental health resilience in offspring of depressed parents: a systematic literature review protocol
Authors: Padaigaitė Eglė , Maruyama Jessica Mayumi , Hammerton Gemma , Rice Frances , Collishaw Stephan 
Published: September 2022

Abstract
Background
Parental depression is associated with a range of mental health conditions and other difficulties in the offspring. Nevertheless, some offspring exposed to parental depression do not develop mental health problems, indicating the presence of protective factors that may buffer parental depression-related risk effects. However, evidence of protective factors that might explain good sustained mental health in offspring of depressed parents is limited and systematic synthesis of these factors is still needed. Therefore, as far as we are aware, this will be the first systematic review that will identify parent, family, child, social, and lifestyle factors associated with mental health resilience in offspring of depressed parents, examine evidence for sex-, developmental stage-, and outcome-specific factors and define mental health resilience in the parental depression context.

Methods
This protocol has been developed according to the PRISMA-P guidelines. Electronic searches will be performed for articles published up to 2022 in PsycINFO, Embase, MEDLINE, Web of Science Core Collection, and Cochrane Library. Two reviewers will independently screen titles/abstracts and full-texts against eligibility criteria, extract the data, and assess the overall quality of evidence. Both observational and RCT studies will be eligible for inclusion if they report offspring mental health resilience/outcome and depressive symptoms or depressive disorder in at least one of the parents/caregivers. Risk of bias will be assessed using The Joanna Briggs Institute (JBI) critical appraisal checklists and The Revised Cochrane risk of bias tool for randomised trials (RoB 2). It is expected that studies will be heterogeneous; therefore, meta-analysis will not be attempted. Studies will be systematically retrieved and collated using numerical, graphical, tabular, and narrative summaries and grouped by their design, scope, or overall quality. Further sub-group analyses will be performed to examine sex-, developmental stage-, and outcome-specific protective factors.

Discussion
The proposed systematic review will be the first to summarise and critically assess quality and strength of evidence of protective factors associated with mental health resilience in offspring of depressed parents. Directions and effect sizes of the protective factors will be discussed as well as differences between the studies, their limitations, and research gaps and future directions. Strengths and limitations of the proposed systematic review will be also discussed. The proposed systematic review findings are expected to help better understand mental health resilience and identify targets for evidence-based prevention and intervention strategies for those in need.

Systematic review registration
A previous version of this systematic review protocol has been registered in the International Prospective Register of Systematic Reviews (PROSPERO) database (www.crd.york.ac.uk/PROSPERO, CRD42021229955).