Summary of findings 1. Summary of findings table ‐ Parenting interventions compared to inactive control (usual care care, attention control, waitlist) for parents who are experiencing CPTSD symptoms or have experienced maltreatment in childhood.

Parenting interventions compared to inactive control (usual care care, attention control, waitlist) for parents who are experiencing CPTSD symptoms or have experienced maltreatment in childhood
Patient or population: parents who are experiencing CPTSD symptoms or have experienced maltreatment in childhood Setting: community‐based programmes, hospitals, out‐patient clinics, public community health centres Intervention: parenting interventions Comparison: inactive control (usual care care, attention control, waitlist)
Outcomes	Anticipated absolute effects* (95% CI)		Relative effect (95% CI)	№ of participants (studies)	Certainty of the evidence (GRADE)	Comments
	Risk with inactive control (usual care care, attention control, waitlist)	Risk with parenting interventions
Trauma‐related symptoms ‐ post‐interventionb	‐	SMD 0.16 SD lower (0.85 lower to 0.53 higher)	‐	33 (1 RCT)	⊕⊝⊝⊝ Very lowc,d	The evidence is very uncertain about the effects of parenting interventions on CPTSD/PTSD symptoms
Psychological wellbeing ‐ post‐interventione	‐	SMD 0 SD (0.69 lower to 0.69 higher)	‐	33 (1 RCT)	⊕⊝⊝⊝ Very lowc,d	The evidence is very uncertain about the effects of parenting interventions on psychological wellbeing (postpartum depression)
Substance use ‐ post‐intervention ‐ not reported	‐	‐	‐	‐	‐	No studies reported data
Parent relationship quality ‐ post‐intervention ‐ not reported	‐	‐	‐	‐	‐	No studies reported data
Parental self‐harm ‐ post‐intervention ‐ not reported	‐	‐	‐	‐	‐	No studies reported data
Parent–child relationship (continuous data) ‐ post‐interventionf	‐	SMD 0.45 SD higher (0.06 lower to 0.96 higher)	‐	153 (2 RCTs)	⊕⊕⊝⊝ Lowg,h,i	Parenting interventions may improve parent–child relationship slightly
Parenting skills ‐ post‐interventionj	‐	SMD 0.25 SD higher (0.07 lower to 0.58 higher)	‐	149 (4 RCTs)	⊕⊕⊝⊝ Lowk,l	Parenting interventions may result in little to no difference in parenting skills
*The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; MD: mean difference; SMD: standardised mean difference
GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect.
See interactive version of this table: https://gdt.gradepro.org/presentations/#/isof/isof_question_revman_web_432966949919695522.

^a Interpretation of importance of SMD effect sizes: < 0.40 = small (trivial) effect (little or no difference), 0.40 to 0.7 = small but important effect (‘slight’ reduction/increase in outcome), > 0.7 = large effect (large reduction/increase in outcome).
^b Outcome: PTSD assessed with The National Women's Study PTSD Module (PNWS‐PTSD), lower scores = less harm.
^c Evidence downgraded 1 level for risk of bias; single study with some concerns about risk of bias.
^d Evidence downgraded 2 levels for imprecision; the 95% CI includes appreciable benefit and appreciable harm (i.e. crosses the threshold for both important benefit (SMD ≥ 0.4) and important harm (SMD ≤ ‐0.4)).
^e Outcome: postpartum depression symptoms assessed with Postpartum Depression Screening Scale (PDSS), lower scores = less harm.
^f Outcomes: parental sensitivity, assessed with Nursing Child Assessment Teaching Scale (NCATS); dyadic reciprocity assessed with Coding Interactive Behaviour System (CIB), higher score = greater benefit.
^g Evidence downgraded 1 level for risk of bias; high risk of bias for one study (49.8% of weight in the meta ‐analysis) and some concerns about risk of bias for the other study.
^h Evidence not downgraded for inconsistency: point estimates differ but confidence intervals overlap and, in both studies, the confidence interval is consistent with both little or no difference and important harm/benefit. (P value Chi2 = 0.11; I2 = 60%).
ⁱ Evidence downgraded 1 level for imprecision; the 95% CI includes ‘little or no’ difference and appreciable benefit (i.e. crosses the threshold for important benefit: SMD ≥ 0.4).
^j Outcomes: Maternal supportive presence (2 studies) assessed with Coding Interactive Behaviour System (CIB) and direct observation; Parental self‐efficacy in nurturance, valuing the child and empathetic responsiveness assessed with Self‐Efficacy for Parenting Tasks Index ‐ Toddler Scale (SEPTI‐TS) (1 study); child caregiving behaviours assessed with Caregiving Helplessness Questionnaire (CHQ) (reverse scored, 1 study), higher score = greater benefit.
^k Evidence downgraded 1 level for risk of bias; high risk of bias for one study (51.8% of weight in the meta‐analysis) and some concerns about risk of bias for all other studies. 
^l Evidence downgraded 1 level for imprecision; the 95% CI includes ‘little or no’ difference and appreciable benefit (i.e. crosses the threshold for important benefit: SMD ≥ 0.4).