Ovarian cancer symptom awareness and anticipated delayed presentation in a population sample

BMC Cancer

Table 1 Overall response rate

	N
Total number of households with connected telephone numbers approached	26,262
Number of households of unknown eligibility*	18,210
Number of households of known eligibility	8,052
Number of households in which the individual declined to take part either during or after assessment of eligibility	1,294
Number of ineligible households*	4,283
Number of eligible households*	3,769
Proportion of households eligible among those assessed for eligibility (%)	46.8
Completed interviews	2,298
Minimum response rate (%) ^†	10.5
Estimated response rate (%)**	46.8

*A household was eligible if one or more people aged 50+ lived in the household.
^†The minimum response rate represents the response rate assuming all households that we could not assess for eligibility were eligible, in other words the lowest possible response rate. It is calculated as the number of completed interviews divided by the number of all possible interviews, i.e. the number of interviews among eligible people plus the number of incomplete interviews among eligible people (refusals, break-offs and non-contacts) plus the number of all households of unknown eligibility (equivalent to the American Association for Public Opinion Research response rate formula 1).
**The estimated response rate represents the response rate after adjusting the size of the denominator for the likely proportion of households that were eligible. It is calculated by assuming that the proportion eligible among households of unknown eligibility is the same as the proportion of those tested for eligibility who were eligible (equivalent to American Association for Public Opinion Research response rate formula 3).

ISSN: 1471-2407