Keeping up to date in general practice.

detail and specific items such as the number of hospital referrals can be extracted fairly quickly by going down the appropriate column, in this case H, on each page. The material contained on the sheets can be used again by rearranging them. As an example, in this survey they were re-arranged in households by class and similar re-arrangements could be continued indefinitely. The flexibility is due to the recording unit being a consultation, hence loss of information is only for the duration of any particular arrangement of the sheets. (Kedward 1962) The great disadvantage of the method is that information is not grouped for easy extraction as it is in the punch card method. It would not be practical if large numbers of consultations were analysed in this way to find out, say, the consulting habits ofwomen over 45 years of age. For this reason it is only suitable as a method for small surveys with a limited number of aims, and it is important that the design of the survey should be carefully prepared.