Table 4.

Mean Utility Value of Taking 1 Pill Daily by Participant Characteristics*

CharacteristicStandard GambleWillingness to PayWillingness to Pay (Free Response)
nMeanP ValuenMeanP ValuenMeanP Value
Age, y
 30–505050.989<0.00015050.9980.30775050.9960.7733
 51–643660.9933660.9883660.990
 ≥651290.991
Sex
 Female5390.990<0.00014820.996<0.00014820.9960.0007
 Male4610.9923890.9903890.991
Race
 Black1590.9870.00011430.9970.82771430.9890.6101
 White6290.9925370.9925370.994
 Other2120.9891910.9971910.997
Education level
 < College degree2840.9890.60262540.9860.24792540.9950.0307
 College or graduate degree7160.9916170.9976170.993
Income level
 <$25 0002240.9850.03401990.9850.16821990.9810.0136
 $25 000–$75 0005160.9924410.9964410.997
 >$75 0002600.9922310.9982310.998
Health rating
 < Very good6210.9890.31765330.9940.75615330.9950.5788
 ≥ Very good3790.9943380.9933380.993
Numeracy level§
 0 Correct2020.9830.00041860.9880.41641860.9910.2710
 1 Correct2880.9882570.9912570.991
 2 Correct5100.9954280.9984280.997
Literacy level
 Inadequate2840.9890.01902520.9870.65792520.9960.6612
 Adequate7160.9916190.9966190.993
Difficulty obtaining pills
 Not difficult5640.9910.00844720.9950.00614720.9930.0047
 Neutral1360.9871180.9981180.997
 Difficult910.988850.993850.993
Difficulty paying for pills
 Not difficult3960.9910.14993280.9930.08673280.9910.1383
 Neutral1900.9901670.9981670.997
 Difficult2040.9891800.9951800.996
No. of times pills taken per day
 <25440.9900.08964920.9940.13504920.9920.0104
 ≥24560.9913790.9933790.997
No. of pills taken per day
 02090.9940.00021960.9900.01851960.9940.0024
 1990.987960.997960.997
 21530.9891440.9961440.996
 3+5390.9914350.9944350.993
  • * Utilities derived using standard gamble method or willingness-to-pay method, as indicated.

  • Participants with age ≥65 years (n=129) removed before calculating mean and P value.

  • P values based on 1-way analysis of variance.

  • § Based on number of answers correct from numeracy screener.

  • Based on response to single-question literacy screener.