Steele J G, Walls A W, Murray J J
Department of Restorative Dentistry, Newcastle Dental School, UK.
Community Dent Health. 1995 Jun;12(2):77-82.
A random sample of adults over 60 years of age was drawn from three different areas of England to take part in a survey of their dental status and needs. The paper describes sampling methods and operational problems in trying to measure oral health in such an age group. The local Family Health Services Authority lists, based on registrations with general medical practices, were used as sampling frames. These proved to be straightforward to manipulate and are believed to be almost complete for the population at this age. Final samples of around 800 individuals in each area were visited at home, representing 53-62 per cent of all subjects who could be contacted, except in one subgroup where only 39 per cent of contacts permitted a visit. There were problems related to difficulty making contact with a proportion of the names sampled. This may have resulted from list errors, illnesses and unrecorded changes of address. A letter from the subjects' family doctors appeared to be an important factor influencing response rates. Systematic bias among subjects refusing a visit was assessed using a follow up postal questionnaire which showed that the edentulous were under-represented in the final (visited) sample by 1-10 per cent, whilst the dentate non-attenders were under represented by 2-13 per cent.
从英格兰三个不同地区随机抽取了一组60岁以上的成年人，参与一项关于他们牙齿状况和需求的调查。本文描述了在试图测量这一年龄组口腔健康状况时的抽样方法和操作问题。以普通医疗诊所的登记记录为基础的当地家庭健康服务管理局名单被用作抽样框架。事实证明，这些名单易于操作，并且据信对于这个年龄段的人群来说几乎是完整的。每个地区约800人的最终样本接受了上门访问，占所有能够联系到的受试者的53%至62%，但有一个亚组中只有39%的被联系者允许访问。在与一部分抽样名单上的人取得联系方面存在问题。这可能是由于名单错误、生病以及未记录的地址变更所致。受试者家庭医生的一封信似乎是影响回复率的一个重要因素。通过后续邮寄问卷对拒绝访问的受试者中的系统偏差进行了评估，结果显示，无牙者在最终（接受访问的）样本中的比例低了1%至10%，而有牙但未就诊者的比例低了2%至13%。
