Valuing the benefits of mobile mammographic screening units using the contingent valuation method

The benefits of improving access to mammographic screening are estimated using a contingent valuation experiment conducted on 458 women in 19 rural Australian towns. The contingent valuation survey provides women with information on mammographic screening and uses a closed-ended format to elicit their willingness to pay for a visit of a mobile mammographic screening unit. Single and double-bounded versions of the discrete response contingent valuation method are employed in the estimation of willingness to pay. The double-bounded contingent valuation approach is shown to be biased due to respondents having a greater disposition to respond 'no' when the bid amount in the follow-up question is higher than the bid amount offered in the initial question. Several approaches to dealing with this bias are examined.