BMC Public Health 2006, 6:211 http://www.biomedcentral.com/1471-2458/6/211 diagnostic accuracy at this cut-off were 60%, 90% and 83% respectively in our previous work [18]. Acceptability survey form A simple, one-page form was used to gather responses to four questions as follows: 1. Women were asked if they remembered completing the EPDS (possible responses were to tick Yes or No). 2. Women were asked what completing the EPDS was like (an open ended question followed by four double-spaced lines across an A4 page in which to answer). 3. Women were asked how comfortable they felt in com- pleting the EPDS (possible responses were arranged on a 5-point Likert scale labelled from Not Comfortable, through Comfortable, to Very Comfortable). This was our central measure of clinical acceptability. 4. Women were asked if they thought it was a good idea to screen new mothers for depression (possible responses were Yes, No and Not sure). Procedure Between January 2002 and July 2005, 8,172 women in Victoria were screened with the EPDS at routine postnatal visits to Maternal & Child Health Centres as part of an ongoing screening and treatment program. The munici- palities involved cover a wide socio-demographic range of neighbourhoods. For these purposes, EPDS scores of ≥ 12 were considered to be positive screening results and scores of <12 were considered negative. The rate of positive screening results was 11.7%. At the end of this period, a retrospective survey of acceptability was begun. This took five months to complete and produced a wide spread of times between screening and survey, thus allowing us to analyse the effect of time since screening on the perceived acceptability and desirability of screening. The acceptabil- ity survey was deliberately structured to encompass roughly equal numbers of: 1) women who screened positive and were referred to our specialist perinatal psychology clinic 2) women who screened positive and were not referred to our clinic 3) women with a negative screening result. This structure helped to ensure a good representation of women with elevated EPDS scores and high numbers of clinically depressed women. To achieve this the survey aimed to reach: 1) all contactable women who had been referred to our clinic after screening with the EPDS (n = 290). NB: most referred women had initially screened positive, but 12 women who screened negative were also referred for assessment (eight were subsequently diagnosed as depressed). 2) a systematic, chronological section of those contactable women who screened positive but were not referred to us (every second such woman in order of date screened), during the same period of time (n = 323) 3) a systematic, chronological section of those contactable women who screened negative and were not referred to us (every twentieth such woman in order of date screened), during the same period of time (n = 307) Postal survey By post, we sent 873 survey forms to women who had completed the EPDS with their Maternal & Child Health Nurses and had consented to take part. Telephone survey Using the same survey form, a research assistant contacted 21 women by telephone and gathered responses to the same set of questions. Face-to-face interview Using the same survey form, 26 women were interviewed face-to-face by a psychologist, using the same set of ques- tions. Statistics We used logistic regression to identify variables affecting both response rates and the acceptability of the EPDS. Sequential modelling began with maximal models in which all putative explanatory variables were fitted simul- taneously. Terms associated with non-significant changes in scaled deviance were removed sequentially until the minimal models necessary to explain the data were reached. Means and Odds Ratios are reported with 95% Confidence Intervals. Frequency distributions were ana- lysed by Chi-squared tests. Furthermore, a systematic cross-section comprising every fifth survey form (in date order) was used to explore women's open-ended responses about the EPDS. Coding was as follows. The comments in each transcript were examined and categorised using an emergent coding approach, following established conventions [20]. Specif- ically, coding of all transcripts was first completed in par- allel by two independent coders, the two lists compared and any disagreements resolved by discussion. Where possible, newly examined transcripts were categorised into already existing categories. For each transcript, the Page 3 of 8 (page number not for citation purposes)