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Detection of Postnatal Depression-Development of the 10-Item EPDS

Detection of Postnatal Depression-Development of the 10-Item EPDS - Clinical Hub, UW Health Clinical Tool Search, UW Health Clinical Tool Search, Questionnaires, Related


British Journal of Psychiatry (1987), 150, 782 786Detection of Postnatal DepressionDevelopment of the 10-item Edinburgh Postnatal Depression ScaleJ. L. COX, J. M. HOLDENand R. SAGOVSKYThe developmentof a 10-item self-reportscale(EPDS)to screenfor PostnatalDepressionin the community is described.After extensive pilot interviews a validation study wascarriedout on 84 mothers usingthe ResearchDiagnosticCriteria for depressiveillnessobtained from Goldberg’sStandardisedPsychiatric Interview. The EPDS was found tohavesatisfactorysensitivityandspecficity,andwas alsosensitiveto changeinthe severityof depressionovertime. The scalecan be completedin about 5 minutesand hasa simplein the secondary prevention of Postnatalmethod of scoring. The use of the EPDSDepressionis discussed.In the last decade several studies (Paykel eta!, 1980;Cox et a!, 1982; Kumar & Robson, 1984; O’Haraet a!, 1984; Watson et a!, 1984) have providedsubstantial confirmation for the earlier fmding ofPitt (1968) that the months following childbirth arefrequently characterised by psychiatric disorder, andthat at least 10-15% of mothers experience a markeddepressive illness at this time.Furthermore, the results of a follow-up studyshowed that postnatal depression was usuallyaccurately recalled by the mothers 3 years later; andthat at least half of the depressed mothers had notrecovered by the end of the first postpartum year(Cox et a!, 1984). The finding that the children ofsuch depressed mothers may show behaviourdisturbance at 3 years (Wrate eta!, 1985) or cognitivedefects at 4 years (Cogill et a!, 1986) suggests thatpostnatal depression may have a long-term negativeimpact on the family.In our earlier study (Cox et a!, 1982), we foundthat 13 of the 101 women interviewed had a markedpost-natal depressive illness and yet the majority ofthese depressed mothers had not received anysustained treatment from their primary care workersnor had they been referred to a psychiatrist; the threewomen who had been referred were not those whowere depressed. This failure to identify depressionin the puerperium, especially when such motherswere usually known to their GP, CommunityMidwife or Health Visitor, was obviously a cause formuch clinical concern.A further difficulty in identifying depressedmothers is that screening scales for depression appearto have a number of limitations when used onchildbearing women. In our earlier study fromEdinburgh, for example, the Anxiety and Depression
Scale (SAD) of Bedford & Foulds (1978) was foundto have uncertain validity; of the 13pregnant womenwho scored 6 + (Foulds’ threshold for personalillness) only three had any form of psychiatricdisorder, while four had minor symptoms only andsixhad no psychiatricillnesswhatsoever(Cox eta!,1983). The 30-item General Health Questionnaire ofGoldberg et a! (1970) has been assessed by Nott &Cutts (1982) for possible use in the puerperium andwas also found to require some slight modifications.These authors reported that 89 (45´ /a) of 200puerperal women scored highly on the 30-item GHQ,but only 37(18´ /a)were found to be psychiatric cases.Similar difficulties with the Beck Depression Inventory(Becketa!,1961)foruseinidentifyingdepressionin the puerperium were reported by O’Hara et a!(1983). In this study only 11 of the 19 women whoscored above the cut-off score fulfilled ResearchDiagnostic Criteria (RDC) for Depression, and ofthe 23 who scored below the cut off there were fourfalse negatives. Furthermore, the finding thatmeasures of self control predicted postnataldepression as measured by the Beck Scale were notconfirmed when a clinical syndrome diagnosis ofdepression was made using Research DiagnosticCriteria suggests that studies using this scale as theonly measure of depression following childbirth maygive misleading results (O’Hara et a!, 1984).The possible explanation for these apparentlimitations of well established scales when used onchildbearing women include their emphasis on thesomatic symptoms of psychiatric disorder whichmay be caused by normal physiological changesassociated with childbearing, as well as the reluctanceof community workers to use questionnaires whichmay be regarded as time-consuming or which782

EDINBURGH POSTNATAL DEPRESSION SCALE 783appear to lack face validity. These limitations mayalso be relevant to a consideration of the ZungDepression Scale (Zung, 1965) for use in thepuerperium.To be useful as a screening test for depressionfollowing childbirth, therefore, a self-report scalemust be fully acceptable to women who may notregard themselves as unwell, or as in need of medicalhelp. The scale needs also to be simple to complete,and not require the health worker to have anyspecialist knowledge of psychiatry. It must havesatisfactory reliability and validity.Furthermore, Williams et a! (1980) haveappropriately emphasised that rating scales whichhad been validated on hospital samples must berevalidated if they are used in community populations where the differences between psychiatric illnessand normality is often less distinct. The earlier workof Snaith (1981, 1983) in this regard was alsoimportant, as he clearly recognised the need tomodify existing scales of depression for use in newspecific clinical situations and in particular was awareof the need to develop a screening questionnaire todetect postnatal depression. Others, such as Kumar(1982) and Cox eta! (1983), had also emphasised thatthis task was an important current research priority.Spurred on by these observations of our colleaguesas well as by the pressing need for primary careworkers to have practical help in identifying postnatal depression, we therefore decided to develop aself-report scale to detect mothers who weredepressed following childbirth.MethodA detailed analysis of the suitability of the Irritability,Depression and Anxiety Scale (IDA) (Snaith et a!, 1978),the Hospital Anxiety and Depression Scale (HAD) (Ziginond& Snaith,1983),and theAnxietyand DepressionScaleofBedford&Foulds(1978)wascarriedout and weeventuallyselected 21 items, including several of our own construction,which we thoughtto be appropriateforthedetectionofpostnatal depression. These items were then tested duringextensive pilot interviews with mothers of young babies.The detailed wording of items, their acceptability to mothersand healthworkers,as wellas their likelihoodof detectingpostnatal depression was then carefully evaluated. Thirteenitems were eventually selected as being those most likelyto detect postnatal depression;sevenof these were itemsconstructed by ourselves and the other six were adaptedfrom the IDA and the HAD.The validity of this 13-itemscale was then establishedon a sampleof 63 purperal womenwho attended a healthcentre in Livingston (see Cox, 1986for details). This studyshowedthat these 13items distinguishedclearlybetweendepressed and non-depressed women, although a rotatedfactor analysis revealed that the two items from the
irritability subscale of the IDA, together with an itemconcerning the enjoyment of motherhood, formed aseparate ¿ non-depression’factor; this latter findingproviding confirmation of Snaith’s earlier observation thatirritability was often identified as a separate mood fromdepression and anxiety. As this analysis of our data hadsuggestedthat the specificityof the scalemightbe increasedby omitting these three items, we decided to carry out afurther validation study using only the 10 items which weremore clearly related to depression. This 10-item scale wouldalso have the advantage of taking less time to complete.The validation study of the 10-itemEPDS to be reportedin this paper was carried out on 84 mothers living inEdinburgh or at Livingston new town. Most of the mothers,who were taking part in a study to determine theeffectiveness of counselling by health visitors in thetreatment of postnatal depression,had been identifiedbytheir health visitors at about 6 weeks following delivery asbeing potentiallydepressed.The health visitors had beenasked to indicate whether, in their opinion, these motherswere ¿ normal’, ¿ depressed’,or wereconsideredas having ¿ problems’.As we envisaged that a useful function of thescale would be to confirm the diagnosis of depression inwomenalreadysuspectedby their primary care worker asbeing possibly depressed, this sample was particularlyappropriate. Wealsoconsideredit important to determinewhether the scale would satisfactorily identify postnataldepression when it was administered in a domesticenvironment. The mother’s home was, therefore, anoptimum setting in which to validate the 10-itemscale; homevisits by health visitors being regarded as an important linkbetween the assessmentof puerperal mothers and othermembers of the primary care team. Mothers in our samplewere interviewed by R.S. using Goldberg’s StandardisedPsychiatric Interview (SPI) (Goldberg eta!, 1970) and themajority of such interviews took place in the mothers ownhome (SPI-l). At this home visit the EPDS was firstcompleted by the mother and was then placed in a sealedenvelopeso that the interviewerremainedblindto the scorewhile subsequently administering the SPI. To prevent anypossible bias effect caused by the interviewer knowing thatthe subject may have been regarded by the health visitoras being ¿ depressed’or as having problems, 12 normalwomenwerealso includedin the sample.The criteriausedfor the diagnosisof a depressiveillnesswerethe ResearchDiagnostic Criteria of Spitzer et a! (1975). Mothers whowereobservedto have a depressedmood but who did notmeet full RDC criteria for depression were, however, alsoseparately identified. As recruitmentof subjects into thestudy was slower than expected, a further 12 women wereinterviewedby J.C. at a local health clinic. Both interviewershad beentrained in the useof the SPI and difficult ratingswerejointlydiscussed.The validationof the 10-itemEPDSwas determined for the total sample by comparing theEPDS scores with the RDC clinical diagnosis of depression.Validation sample ResuftsThe mean age of womenwas 26 years, and that of theirbabieswas3 months.Seventy-fivepercenthad had normal

in some clinical or research settings for actual cases ofdepression not be missed, our data suggest that the faileddetection of cases can be reduced to under 10% with a cutoff score of 9/10.Whenanalysisof our data wascarriedout on onlythosewomen (n= 60) interviewed by R.S. (excluding the 12womenwith no previouslyidentified problems, as wellasthe 12subjects interviewedby J.C. at the Health Centre)the optimum thresholdscorewasalmost the sameas in thelarger sample, sensitivity 85´ /a, specificity 77%, the positivepredictivevalue having increased to 83´ /a.The split-halfreliability of the scale was found to be 0.88, and thestandardised a-coefficient 0.87.Sensitivityto change in the severityof depressionovertimewasalsoestablishedon a subsampleby comparingtheEPDS scoreat the first interview(EPDS-l), whenmothersweretaken into the counsellinginterventionstudy,withthatobtainedat the li-week follow-upinterview.At this secondhome interviewtheEPDS was completedfora secondtime(EPDS-2), and a repeat SPI (SPI-2) was carried out, theinterviewer again remaining blind to both the EPDS-l andthe EPDS-2 scores.Analysisof thisdata showedthat thosemotherswhoweredepressed according to RDC criteria at both interviews(n = 15), showed no significant difference between theirEPDS-1 (16.5) and EPDS-2 (15.38) mean scores on thesetwo occasions, whereas mothers who were depressed atInterview 1 but not at Interview 2 (n = 16) had a reductionof score betweenEPDS-l and EPDS-2 which was highlysignificant. (EPDS-i mean score= 15.8, EPDS-2 meanscore= 9.8, t= 3.72, P= 0.002). The EPDS-2 score in allbut one subject fell to below the threshold of 12/13; themother whoseEPDS-2 score increased, but who was notdepressed, had a probable cancer of the cervix and wasdiagnosed as having an anxiety neurosis.Analysisof the possibleinfluenceon the EPDS scoreofanother family memberbeing present when the scalewascompleted suggested that under these circumstances womentended either to exaggerate, or to minimise, their psychiatricproblems. Thus three subjects who had the highest ¿ false ¢¿ positive’score, and three of the four ¿ falsenegatives’,hadnot been alone when they were interviewed.
784 COX ET ALdeliveries,15%Caesarian sectionsand a further 10,1.hadforcepsdelivery.The majority (81%)weremarried, whilst13´ !. had a permanent partner. Only 6´ /a were singleparents. Social class distribution (according to husband’s,or partner’s occupation where one was present, or accordingto the mother’s previous occupation in the case of singleparents) was as follows: Social Class 11:7’!., 111:35´ !.,IV:3l´ /., V:27´ /o.Validation of the 10-Item EPDSThe results of the validation of the 10-itemEPDS are shownin Fig. 1.A threshold score of 12/13 was found to identify all ofthe 21 women with an RDC diagnosisof Definite MajorDepressive Illness and two of the three women withProbable Major DepressivelUness.Four of the 11womenwith Definite Minor Depressionwere false negatives,i.e.theyscored12or below,and therewere11 ¿ falsepositives’,although six of these 11 women had depressive symptomsbut did not meet full Research Diagnostic Criteria fordepression. The subject with the highest false positive score(21) had a marked personality disorder; while the threewomen with a psychiatric diagnoses other than depressionallscoredbelow thecut-off.The sensitivityof the EPDS, the proportion of RDCdepressed women (n = 35) who were true positives (n = 30),was 86´ /a;the specificity, proportion of non-depressedwomen(n= 49)who weretrue negatives(n= 38),was78´ /a.The positive predictive value, the proportion of womenabove threshold on the EPDS (n=41) who met RDC criteriafor depression (n = 30), was 73´ /a.As it is important30
20
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DiscussionOur study has shown that the 10-item PostnatalDepression Scale, which was derived from the earlierwork of Snaith, had satisfactory validity, split-halfreliability and was also sensitive to changes in theseverity of depression over time. Furthermore, wefound that the scale was fully acceptable to the childbearing women and was usually completed within5 minutes. The simple method of scoring was anadvantage and the health visitors recognised that thescale would greatly assist them in the detection ofmothers who were depressed postpartum.We believe it to be a substantial advantage thatthis validation study of the 10-item scale was carriedout in a community setting and on women who were
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¢¿ ¢¿ No,ud other Depressed Mvior Minor Mojor M@ordiogrusis mood pivbable definils prob@1s definiten:33 n:4 n’12 n:O i;:11 ,,:3 n=21.@___fl@ dsprsss,on .FIG. 1 Validation of Edinburgh Postnatal Depression Scale.

EDINBURGH POSTNATAL DEPRESSION SCALE 785as close as possible to mothers regarded by theirprimary care workers as having problems. Our datanevertheless suggested that sensitivity and specificityof the scale may be increased if it is completed whenother family members are not present.It seems likely that the scale will be usefulin the routine work of community health workers(e.g. health visitors, community psychiatric nursesand General Practitioners) and assist to identifypostnatal depression in mothers thought by theirhealth worker to be at risk. It may also be ofuse in treatment studies of postnatal depression whencarried out on mothers living in the community.Our data suggested that women who scoredabove a threshold of 12/13 were most likely to besuffering from a depressive illness of varying severity,and should therefore be further assessed by theprimary care worker to confirm whether or notclinical depression is present. The EPDS is nota substitute for this clinical assessment, and ascore just below the cut-off should not be takento indicate the absence of depression, especiallyif the health professional has other reasons toconsider this diagnosis. Our data also suggest thata threshold of 9/10 might be appropriate if the scalewas considered for routine use by primary careworkers.We now plan to validate the scale for possibleuse during pregnancy and also to determine itsusefulness in other populations. The scale could, forexample, be administered by a computer at amother’s visit to an antenatal or postnatal clinic,and it may be useful as a more general screeningscale for depressive illness. The revalidation ofthe scale for use in these other clinical settingsmust be carried out, however, before this wideruse is recommended.AcknowledgementsWe are indebted to the many GPs and Health Visitors atLivingstone and Edinburgh who collaborated with us. We thankMr R. J. McGuire for his statistical advice and for encouragementat various stages of the study. The research was generouslysupported by a grant from the Scottish Home and HealthDepartment. ReferencesBanroan, A. & Fouws, 0. (1978)Dehisions-Symptoms-States.Stateof Anxiety anti Depression(Manual) Windsor: NationalFoundation for Educational Research.Bacic, A. T., WAJW,C. H. & MENDEISON,M. ci a! (1961) Aninventory for measuring depression. Archives of GeneralPsychiatry, 4, 561 571.
COGILL,S. R., CAPLAN.H. L., ALEXANDRA.H., ROBSON,K. M.& Ku@t@a,R.(1986)Impactofmaternalpostnataldepressionon cognitive development of young children. British MedicalJournal, 292, 1165 1167.Cox, J. L. (1986) Postnatal Depression ¿ A Guide for HealthProfessionals. Edinburgh: Churchill Livingstone. ¿ , Co@oR, Y. & KENDELL, R. E. (1982) Prospective study ofthe psychiatric disorders of childbirth. British Journal ofPsychiatry, 140, 111 117. ¿ , ¿ , HENDERSON, 1., Mc0urna, R. J. & KENDELL, R. E.(1983)Prospective study of the psychiatric disorders of childbirthby self report questionnaire. Journal of Affective Disorders, 5,1 7. ¿ , ROONEY, A., THOMAS, P. F. & W@m, R. W. (1984) Howaccurately do mothers recall postnatal depression? Further datafrom a 3 year follow-up study. Journal of PsychosomaticObstetrics and Gynaecology, 3, 185 189.GOLDBERG,D. P. (1972) The Detection of Psychiatric Illness byQuestionnaire. Maudsley Monograph, 21, Oxford: OxfordUniversity Press. ¿ . COOPER, B.. EASTWOOD, M. R., KEDWARD, H. B. &SHEPHERD, M. (1970) A standardised psychiatric interview foruse in community surveys. British Journal of Preventive andSocial Medicine, 24, 18023.Kui@u@a.R. (1982)Neuroticdisordersin childbearingwomen. InMotherhood and Mental Illness, eds I. Brockington & R. Kumar.London:AcademicPress. ¿ & ROBSON, K. M. (1984) A prospective study of emotionaldisorders in childbearing women. British Journal of Psychiatry,144, 35 47.Noi-r, P. N. & Cui-rs, 5. (1982) Validation of the 30-item GeneralHealth Questionnaire in postpartum women. PsychologicalMedicine,12, 409 413.O’H@a@,M. W., REHM, L. P. & CAMPBELL,S. B. (1983)Postpartumdepression:a roleforsocialnetworkand lifestressvariables.JournalofNervousandMentalDisease,171,336 341. ¿ , NEUNABER, D. J. & Zsicosici, E. M. (1984) Prospectivestudy of postpartum depression: prevalence, course andpredictive factors. Journal of Abnormal Psychology, 93,158 171. ¿ , E@tt@s, E. M., FL@rcnea, J. & RASSABY, E. 5. (1980) Lifeevents and social support in puerperal depression. British Journalof Psychiatry, 136. 339-346.Pirr, B. (1968) ¿ Atypical’depression following childbirth. BritishJournal of Psychiatry, 114, 1325 1335.SNAITh. R. P. (1981) Rating scales. British Journal of Psychiatry,138,512 514. ¿ (1983) Pregnancy-relatedpsychiatricdisorder.BritishJournalof Hospital Medicine, 29, 450 456. ¿ , CoP4smwroPouLos, A. A., JARDINE, M. Y. & MCGUFFIN, P.(1978) A clinical scale for the self-assessment of irritability.British Journal of Psychiatry, 132, 164 171.SPITZER. R., ENDIcorr, J. & ROBINS, E. (1975) Research DiagnosticCriteria. Instrument No. 58. New York: New York StatePsychiatric Institute.WATSON, J. P., ELLIOT-r, S. A., Ruoc, A. J. & BROUGH, D. I.(1984) Psychiatric disorder in pregnancy and the first postnatalyear. British Journal of Psychiatry, 144, 453-462.WILuAMS, P., T@apioi’oisjcy, A. & H@, D. (1980) Case definitionand caseidentificationin psychiatricepidemiology:reviewandassessment.PsychologicalMedicine,10, 101 114.WSAm, R. M., ROONEY,A. C., THOMAS,P. F. & Cox, J. L. (1985)Postnatal depression and child development: a three year followup study. British Journal of Psychiatry, 146, 622-627.ZIGMOND, A. S. &@ R. P. (1983) The Hospital Anxiety andDepression Scale. Acta Psychiatrica Scandinavica, 67, 361-370.ZUNG.W. W. K. (1965)A self-ratingdepressionscale.Archivesof General Psychiatry, 12, 63.

786 COX ET ALAppendixEdinburgh Postnatal Depression Scale (EPDS)The Edinburgh Postnatal Depression Scale (EPDS) has beendeveloped to assist primary care health professionals to detectmothers suffering from postnatal depression; a distressing disordermore prolonged than the ¿ blues’(which occur in the first week afterdelivery) but less severe than puerperal psychosis.Previous studies have shown that postnatal depression affects atleast 10´ of women and that many depressed mothers remainuntreated. These mothers may cope with their baby and withhouseholdtasks,buttheirenjoymentoflifeisseriouslyaffectedand it is possible that there are long-term effects on the family.The EPDS was developedat health centresin LivingstonandEdinburgh. It consists of ten short statements. The motherunderlines which of the four possible responses is closest to howshehasbeenfeelingduringthepastweek.Mostmotherscompletethe scalewithout difficultyin less than 5 minutes.The validationstudyshowedthat motherswho scoredaboveathreshold 12/13 were likely to be suffering from a depressive illnessof varying severity. Neverthelessthe EPDS score should notoverride clinical judgement. A careful clinical assessment shouldbe carried out to confirm the diagnosis. The scale indicates howthe mother has felt during the previous week, and in doubtful casesit may be usefully repeated after 2 weeks. The scale will not detectmothers with anxiety neuroses, phobias or personality disorders.
InstructIons for users1. The mother is asked to underline the response which comesclosestto how she has been feelingin the previous7 days.2. AU ten items must be completed.3. Care should be taken to avoid the possibilityof the motherdiscussingher answerswith others.4. The mother should complete the scale herself, unless she haslimited English or has difficulty with reading.5. The EPDS may be used at 6-8 weeks to screen postnatal women.Thechildhealthclinic,postnatalcheck-upor a homevisitmayprovide suitable opportunities for its completion.EDINBURGHPOSTNATALDEPRESSIONSCALE(EPDS)J. L. Cox, J. M. Holden, R. SagovskyDepartment of Psychiatry, Universityof EdinburghName:Address:Baby’s age:As youhaverecentlyhad a baby,wewouldliketo knowhowyouare feeling. Please UNDERLINE the answer which comes closestto how you have felt IN THE PAST7 DAYS,not just how youfeel today.Here is an example,alreadycompleted.I have felt happy:Yes, all the timeYes most of the timeNo, not very oftenNo, not at allThiswouldmean: ¿ Ihavefelthappymostof the time duringthepast week. Please complete the other questions in the same way.
In the past 7 days:1. I have been able to laugh and see the funny side ofthingsAs much as I always couldNot quite so much nowDefinitelynot so much nowNot at all2. I have looked forward with enjoyment to thingsAs much as I ever didRather less than I used toDefinitelylessthan I used toHardly at all* 3. I have blamed myself unnecessarily when things wentwrongYes, most of the timeYes, some of the timeNot very oftenNo, never4. I have been anxious or worried for no good reasonNo, not at allHardly everYes, sometimesYes, very often* 5. I have felt scared or panicky for no very good reasonYes, quite a lotYes, sometimesNo, not muchNo, not at all* 6. Things have been getting on top of meYes, most of the time I haven’t been able to copeat allYes, sometimes I haven’t been coping as well asusualNo, most of the time I have coped quite wellNo, I have been coping as well as ever* 7. I have been so unhappy that I have had difficultysleepingYes, most of the timeYes, sometimesNot very oftenNo, not at all* 8. I have felt sad or miserableYes, most of the timeYes, quite oftenNot very oftenNo, not at all* 9. I have been so unhappy that I have been cryingYes, most of the timeYes, quite oftenOnly occasionallyNo, never*10. The thought of harming myself has occurred to meYes, quite oftenSometimesHardly everNeverResponse categories are scored 0. 1.2, and 3 according to increased severityof the symptom.Itemsmarkedwithan asteriskarereversescored(i.e. 3,2, 1and0).Thetotalscore is calculated by adding together the scores for each of the ten items.Users may reproduce the scalewithout furtherpermission providingthey respectcopyright (whichremains with the British Journal of Psychiairy)by quoting thenamesof the authors, the titleand the sourceof the paper in all reproducedcopies.L. Cox, MA,DM,FRCP(Edin),FRCPsych,Professor of Psychiatry, Department of Postgraduate Medicine,University of Keele. Consultant Psychiatrist, City General Hospital, Stoke-on-Trent, formerly SeniorLecturer, Department of Psychiatry, University of Edinburgh; J. M. Holden, BSc, SRN, HVCert, ResearchPsychologist; R. Sagovsky, MB, ChB,MRCPSyCh,Research Psychiatrist, Department of Psychiatry, Universityof Edinburgh*Correspondence: University of Keele, Thornburrow Drive, Hartshil, Stoke-on-Trent, Staffs 517 7QB