The experience of using random digit dialling methods in a population-based chronic pain study.
OBJECTIVE
To describe response rates and call characteristics using random digit dialling (RDD) methods in a population-based prevalence study of chronic pain; to compare respondent characteristics according to telephone number listing status.


METHODS
A RDD telephone study of chronic pain was conducted using computer-assisted telephone interview (CATI) methods in the Northern Sydney Area in 1998.


RESULTS
Unlisted number respondents (18.5%) were younger, had a higher proportion of males, and were less likely to live in households with three or more eligible adults. There was no difference in chronic pain status between the two groups. The overall response rate was 73.4% (unlisted number group 66.3%; listed number group 75.0%). Answering machine messages boosted response rates (79.7%). 10.9% of unlisted numbers used in the study resulted in completed interviews, compared with 31.3% of the listed numbers used.


CONCLUSIONS
The relatively high response rate obtained, differences in characteristics associated with listing status and reduction in sampling bias provided by using RDD methods have to be balanced against the differential response rates between listed and unlisted number groups and higher costs (including opportunity costs). IMPLICTIONS: Published data on the experience of using RDD methods can assist public health researchers in deciding whether to use these methods in telephone surveys.
Blyth
Fiona M
FM
Pain Management and Research Centre, University of Sydney, New South Wales, Royal North Shore Hospital, St Leonards. fblyth@doh.health.nsw.gov.au
March
Lyn M
LM
Shellard
David
D
Cousins
Michael J
MJ
D000328:Adult; D002908:Chronic Disease / Q000453:epidemiology; D003625:Data Collection / Q000379:methods; D005260:Female; D006306:Health Surveys; D006801:Humans; D007407:Interviews as Topic / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009517:New South Wales / Q000453:epidemiology; D010146:Pain / Q000453:epidemiology*; D011159:Population Surveillance / Q000379:methods; D015995:Prevalence