Consumer preferences for hearing aid attributes: a comparison of rating and conjoint analysis methods

Abstract

Low utilization of hearing aids has drawn increased attention to the study of consumer preferences using both simple ratings (e.g., Likert scale) and conjoint analyses, but these two approaches often produce inconsistent results. The study aims to directly compare Likert scales and conjoint analysis in identifying important attributes associated with hearing aids among those with hearing loss. Seven attributes of hearing aids were identified through qualitative research: performance in quiet settings, comfort, feedback, frequency of battery replacement, purchase price, water and sweat resistance, and performance in noisy settings. The preferences of 75 outpatients with hearing loss were measured with both a 5-point Likert scale and with 8 paired-comparison conjoint tasks (the latter being analyzed using OLS [ordinary least squares] and logistic regression). Results were compared by examining implied willingness-to-pay and Pearson's Rho. A total of 56 respondents (75%) provided complete responses. Two thirds of respondents were male, most had sensorineural hearing loss, and most were older than 50; 44% of respondents had never used a hearing aid. Both methods identified improved performance in noisy settings as the most valued attribute. Respondents were twice as likely to buy a hearing aid with better functionality in noisy environments (p < .001), and willingness to pay for this attribute ranged from US$2674 on the Likert to US$9000 in the conjoint analysis. The authors find a high level of concordance between the methods-a result that is in stark contrast with previous research. The authors conclude that their result stems from constraining the levels on the Likert scale.

Figure 1.

An example of attribute valuation via rating on a Likert scale Note: This is an example of what the Likert scale looked like as presented to respondents. The description of what “quiet environment” meant is in the middle box. Respondents would tick one box with how important the characteristic of the hearing aid was to them.

Figure 2.

An example of attribute valuation via choice-based conjoint analysis Note: This is an example of one of the choice tasks. The levels of each characteristic are sorted into a variety of hypothetical hearing aids. The respondents were asked to select which of the two they preferred and were asked to make eight choices between pairs of different hearing aids.

Figure 3.

Estimates of willingness-to-pay for attributes Note: The willingness-to-pay for the attributes gives an estimate of how valuable each characteristic is to respondents. Here we see it is worth from nearly US$3,000 to US$9,000 to have a hearing aid with better functionality in noisy environments.