Ward E M, Kramer S, Meadows A T
Am J Epidemiol. 1984 Oct;120(4):582-91. doi: 10.1093/oxfordjournals.aje.a113920.
A study of random digit dialing as a method of control selection was conducted as part of a matched case-control study of risk factors for neuroblastoma. The study was conducted in 1981-1982 in the Greater Delaware Valley region. Participation involved parents submitting to a 2-4-hour telephone interview. Potential control telephone numbers were selected by substituting the last two digits of the case family's telephone number with randomly selected digits. Successive random telephone numbers were called until a family with a child matching the case by year of birth plus or minus three years and race who agreed to participate was identified. A total of 3,245 telephone numbers were dialed to select controls for 101 cases, an average of 32.1 telephone numbers per case. Among 1,908 residential households contacted, 25.5% refused to give information about household characteristics. Of households with known characteristics, 45% had children under 25 years of age and 14.9% had a child eligible for the study. Among 181 households invited to participate, 101 agreed. For 18.6% of all calls, residential respondents were randomly offered $10 as an inducement to participate. This inducement did not significantly influence participation rates among families invited to participate.
作为神经母细胞瘤危险因素配对病例对照研究的一部分，开展了一项关于随机数字拨号作为对照选择方法的研究。该研究于1981 - 1982年在大特拉华谷地区进行。参与研究要求家长接受2 - 4小时的电话访谈。通过用随机选取的数字替换病例家庭电话号码的最后两位数字来选择潜在的对照电话号码。依次拨打随机电话号码，直到找到一个孩子的出生年份与病例相差三岁以内且种族匹配并同意参与的家庭。总共拨打了3245个电话号码为101例病例选择对照，平均每个病例拨打32.1个电话号码。在联系的1908个住户中，25.5%拒绝提供家庭特征信息。在已知特征的住户中，45%有25岁以下的孩子，14.9%有符合研究条件的孩子。在邀请参与的181个住户中，101个同意参与。在所有电话中，有18.6%向住户受访者随机提供10美元作为参与的诱因。这种诱因对受邀参与家庭的参与率没有显著影响。
