Appendix

Appendix 3: Methodological quality of selected studies

Adewuyaet.al.2006 / Ayers1999 / Baeckeet.al.2009 / Cohenet.al.2004 / Creedy1999 / Engelhardet.al.2002 / Hoedjesetal.2001 / Lev-Wieseletal.2009 / SorensonTschetter2010 / Stramroodetal.2010 / Stramroodetal.2011
Wasthecohortrecruitedinanacceptableway(toassesstheassociationbetweenPTSD(symptoms)andseverematernalmorbidity(SMM)? / Yes / Unclear - excluded women with elective caesarean section / Unclear -recruitmentprocess:uncertain / Unclear -excludedwomenwithriskofbaby / Unclear -excludedwomenwithmedicalrisk / Unclear -recruitedonlyprimiparas / Unclear -recruitedonlywomenwithpreeclampsia / Unclear -recruitmentprocess:uncertain / Unclear -recruitedwomenusingnewspaperandpublicphonebook / Unclear -excludedmultiplepregnancyetc. / Yes
-nohealthycontrol
(samplerepresentativeness) / -smallsample† / -smallsample† / -smallsample† / -smallsample† / -smallsample† / -smallsample†
WastheSMMaccuratelymeasuredtominimizebias? / Unclear hospitaladmission:reasonuncertain / Unclear -combineddifferenttypesofcomplicationswithlessseverecases‡ / Yes / Unclear -combineddifferenttypesofcomplicationswithlessseverecases‡ / Unclear -combineddifferenttypesofcomplicationswithlessseverecases‡ / Yes / Yes / Unclear -combineddifferenttypesofcomplicationswithlessseverecases‡ / Unclear -definition,typeanddatasourceofcomplication:uncertain‡ / Yes / Unclear -datasource:self-report‡
-datasource:self-report‡ / -datasource:uncertain‡ / -datasource:self-report‡ / -datasource:partiallyself-report‡
WerePTSDorPTSDsymptomsaccuratelymeasuredtominimizebias? / Yes / Yes / Yes / Yes / Yes / Yes / Yes / Yes / Unclear -scale:validitynotestablished‡ / Yes / Yes
Havetheauthorsidentifiedallimportantconfoundingfactors / Yes / Yes / No-pre-existingpsychologicalissues:notmentioned / Yes / Yes / No-pre-existingpsychologicalissues:notmentioned / Yes / Yes / No - pre-existing psychological condition: not mentioned / Yes / Yes
Havetheytakenaccountoftheconfoundingfactorsinthedesignand/oranalysis? / Yes / No -pre-existingPTSDwascontrolledfor,butnotothers / No -numbersofpre-existingpsychologicalissues:notcontrolledfor / Yes, except for controlling for pre-existing PTSD / Yes, except for controlling for pre-existing PTSD / No -numbersofpre-existingpsychologicalissues:notcontrolledfor / No -assessmenttimewascontrolledfor,butnotothers / Yes / No -unadjustedanalysis / Yes / Yes, except for controlling for pre-existing PTSD
Wasthefollowupofsubjectscompleteenough?(eg.thepersonsthatarelosttofollow-upmayhavedifferentoutcomesthanthoseavailableforassessment) / Yes / Yes / Unclear / Yes / Yes / Yes / Yes / Unclear / Unclear / Unclear / Unclear
-non-responsebiasclearlydiscussed / -non-responsebias:notdiscussed‡ / -non-responsebiasclearlydiscussed / -non-responsebiasclearlydiscussed / -non-responsebiasclearlydiscussed / -non-responsebiasclearlydiscussed / -smalldropoutrate,butwomenwhodidnotconsentattherecruitmentwasnotreported‡ / -non-responsebias:notdiscussed‡ / -womennotwillingtoparticipatewasnotreported‡ / -non-responsebias:notassessed‡
Wasthefollowupofsubjectslongenough? / Yes / Yes / Yes / Yes / Yes / Yes / Yes / Yes / Yes / Yes / Yes
Otherlimitations / Cross-sectional / -- / -- / -- / -- / Retrospectively collected key variables up to previous 2 years‡ / -- / -- / cross-sectional / -- / Cross-sectional

Note: ‡ There is a possibility of information bias due to misdiagnosis, recall bias or missing data (ie. refusals, non-participation, non-response). † There is a possibility of low statistical power.