the reticent users were asked simply , as described above , to state the methods they had ever used and the stage in family building when they started these practices . they were not asked for further details in view of their original reluctance to admit to practice . in this attempt to elicit contraceptive histories , attention was directed towards minimising any embarrassment . the relevant questions were put at the end of the questionnaire to allow time for the interviewer to gain the informant &apos;s confidence and the list of contraceptives included both medical and colloquial names for the various contraceptive methods . the use of the card with its numbered list prevented the informant from having to mention the methods by name . in the event interviewers found little difficulty with these birth control questions ; reports from supervisors suggest that once an informant had embarked on the questionnaire , he or she co-operated to the end . only 17 refused to say whether or not they had ever practised any form of birth control , and a further 20 informants , who were found to have taken some action to control conception , refused to indicate the methods they had used ; one commented : I think it is a very private matter and would rather not discuss it . this bears out the American study experience : only 10 of the 2,713 wives who were interviewed were unwilling to answer the questions about their attempts to avoid conception ; this was less than the refusal rate for their questions about income and the usual refusal rate for income questions in other sample surveys . despite the apparent ease of the interview situation and the low refusal rate on these birth control questions , possibilities for error and reticence exist . as mentioned in part 1 of this paper , nearly half the informants were interviewed in the presence of relatives , friends or children ; although it seems that the presence of these people did not seriously affect the response to questions on contraceptive practice , they may occasionally have been an inhibiting factor , even though informants were not required to mention methods by name . also , although the informants seemed to understand the terms on the card showing the list of contraceptives , it is possible that incorrect answers were given by a few who only knew a different colloquial name for the method used . the following analysis shows that a large majority of the informants only ever used one contraceptive method or group of methods simultaneously ; however , it is possible that a few informants , weary at this stage in a long interview , may not have taken the trouble to outline their whole contraceptive history and only mentioned the method they considered the most important . lastly , the interviewers , though skilled and experienced at questioning diverse people on a wide range of topics , were not specifically trained as those engaged in the Lewis-Faning and the American study had been for this almost clinical aspect of the inquiry . differential response by male and female informants . one or more of the above may account for the surprising finding that , in every cohort and social class , birth control practice was mentioned more often by men than by women . some 74 per cent of the male informants married since 1930 reported practising contraception in their first marriages against only 65.1 per cent of the female informants . the questions had been designed ( see p 122 ) to obtain each couple &apos;s contraceptive practice and not just the action taken by the informants alone , and hence similar results were anticipated from male and female informants . perhaps this was a naive expectation , since psycho-sexual factors , particularly in this culture may tend to inhibit women on the subject and possibly in turn lead men in some cases to overstate their practices . a complete understanding of this differential sexual response is obviously impossible , but a clearer examination of the method of questioning suggests some explanation and makes possible an assessment of the significance of this finding on the validity of the results on birth control methods . questioning on family planning opened with an inquiry about attitudes . Q 182a : many married couples do something to limit the size of their families and to control when their children come . how do you feel about this ? replies showed that male informants married since 1930 fully approved of birth control more frequently than female informants ; in all 68.9 per cent of the men against 63.9 per cent of the women , but the differences were especially marked amongst those married in the 1940s , where 72.2 per cent of men approved against only 60.2 per cent of women . this questioning on personal attitudes was followed by the enquiries about practice described above . response to the first question shows the main sex differential ; 57.5 per cent of the male informants married since 1930 answered positively ( in our terminology declared themselves to be avowed users ) as against 47.2 per cent of the female informants ; this differential operated in all cohorts and classes , but , as with the attitude question , was more marked in the 1940-49 cohort ( 62.1 per cent of male informants to 46.1 per cent of female informants ) and particularly amongst the skilled manual and other manual workers in this cohort . it was only when informants had declared their use of contraception in this way that they were asked the methods they had used and were shown the full list of appliance and non-appliance methods . at this stage the same proportion of each sex reported using only non-appliance methods including withdrawal , but the female informants reported less use of appliance methods . closer examination revealed , as was to be expected , that as many female informants as male informants had reported use of the cap ; hence the difference lay essentially in reports of the sheath . we had expected the difference to lie in reports of male methods since it seems possible that some female informants who disapproved of birth control might quite reasonably have denied practice if their husbands were responsible for the methods used , and particularly as the request for information on the couple &apos;s methods was not specifically repeated in the wording of the question on methods used ( Q 188 ) ; but we thought this difference would show up more in the proportion reporting withdrawal . however , in all cohorts as many women as men married since 1930 had , by this stage in the questioning , reported the practice of withdrawal . but perhaps , and Freedman and Whelpton mention this possibility , women responded to the positive suggestion of husband is careful , withdraws and some reported this method when in fact their careful husbands had used the sheath . it will be remembered from p 123 ( Q 186 ) that all those denying birth control practice were shown a numbered list of non-appliance methods and asked to state , by number which , if any , they had used . in some of the cohorts and classes where the sex differential in the proportion of avowed users was most marked some of the leeway was made up by a greater proportion of women admitting to the use of these non-appliance methods ( in our terminology declaring themselves to be reticent users ) , particularly in the 1940-49 cohort where a further 21.1 per cent of the female informants became reticent users as against only 16 per cent of the male informants ( the proportion for the other manual group showed an excess of 10 per cent for women over men ) . it should be remembered here that for these informants this was the first time they had been shown a list of methods and also that this list only included non-appliance methods . interestingly , at this point , more women than men mentioned use of withdrawal and significantly more in the seriously affected 1940-49 cohort , supporting the theory that some of the sex differential on avowed use was due to the failure of women to report practice when their husbands had taken the contraceptive action . also , since these informants were confined to non-appliance methods , it is possible that some women reported withdrawal when in fact their husbands had used the sheath . the combined answers of the avowed and reticent users together give us the total extent of eventually admitted birth control practice . this shows a steady differential in all cohorts including the 1940s , of approximately 10 per cent more admitted practice for male informants than females ; the difference lies , particularly in the 1940-49 cohort in the proportion of male and female informants reporting use of appliance methods . from the probably genuine sex differential in personal attitudes to contraception , through the intensive , carefully worded but perhaps too closely defined method of questioning , some female informants may have failed to reveal their birth control practices , particularly where their husbands were responsible for the contraceptive measures , and others may have recorded husband is careful , i.e withdrawal , when in fact he used the sheath . in assessing the significance of this , particularly in relation to the analysis of patterns of contraceptive practice to follow , it seems most relevant to examine the effect on the internal consistency of the all user group , and more particularly the avowed user group . here we find that the differential response by male and female informants has not seriously disturbed the balance of methods reported by the two sexes . amongst the all user group the proportions reporting any appliance method and using only non-appliance methods show an unbalance for the sexes only in the 1940-49 cohort , and even these differences are barely significant at the 5 per cent level . the pattern for the avowed users is even better ; in all cohorts and classes the frequency of methods reported by male and female informants is similar . since the analysis of birth control methods and contraceptive histories is concerned essentially with the patterns of methods reported by the users and particularly the avowed users , we have felt it justified to continue the analysis of birth control methods for all informants , male and female combined . the above poses obvious questions about the completeness of the data to follow . undoubtedly the results understate the actual extent of practice and probably the use of some methods ; nevertheless , this is a first attempt to get at the birth control experiences of a national sample and the findings appear to be consistent in their trends , and at least point to changes over time in contraceptive behaviour , even if they do not provide an absolutely complete history of birth control experiences throughout the population . use of different birth control methods . the informants who admitted to the practice of birth control , whether at once or after probing , indicated the various contraceptive methods they had used during their married lives . many reported that two or more methods had been used , either simultaneously or in succession , so the number of reports of methods exceeds the total of users . to show the extent to which the various methods are used and their changing popularity over the period , table 1 treats each method separately and gives the proportion of users reporting each method . it also contrasts the marriage survey with the American study . table 1 shows the overwhelming importance among marriage survey users of the two male methods : the sheath is reported by almost half these users and withdrawal by 44 per cent . the next most popular method is safe period but it is only reported by 16 per cent of the informants , followed by cap ( 11 per cent ) and pessary and gels ( 10 per cent ) . comparison of the three cohorts shows some changes . there is a significant trend away from withdrawal and towards the cap ; the increase in the proportion of sheath users is not quite significant . the American data can be compared with the marriage survey totals column . although the sheath is the most popular method in both countries , the frequency of other methods is significantly different . withdrawal , Britain &apos;s next most frequently adopted method , is used by only 15 per cent of the American sample , and instead there is greater reliance on the female methods : cap , safe period and douche . in Britain there are nearly twice as many reports of the use of male methods as female ( 92.8 per cent to 48.2 per cent ) , whereas in the U.S.A the proportions are reversed . 