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(Mis)predicting adaptation to adverse outcomes: New evidence from the medical domain

(Mis)predicting adaptation to adverse outcomes: New evidence from the medical domain. George Loewenstein (presentation at HDGC 1/22/03). Collaborators (partial list): Peter Ubel, M.D. John Hershey, Ph.D. Jonathan Baron, Ph.D. David A. Asch, M.D., M.B.A. Christopher Jepson, Ph.D.

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(Mis)predicting adaptation to adverse outcomes: New evidence from the medical domain

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  1. (Mis)predicting adaptation to adverse outcomes: New evidence from the medical domain George Loewenstein(presentation at HDGC 1/22/03) • Collaborators (partial list): • Peter Ubel, M.D. • John Hershey, Ph.D. • Jonathan Baron, Ph.D. • David A. Asch, M.D., M.B.A. • Christopher Jepson, Ph.D. • Angela Fagerlin, Ph.D. • Julie Lucas, B.B.A. • Jason Riis

  2. Adaptation • Material (behavioral) • Hedonic

  3. Predictions of adaptation General finding: people underpredict their own speed of adaptation (both negative and positive) • Loewenstein & Frederick, 1997 (diverse, including income) • Gilbert et al. 1998 (e.g., tenure) • Schkade & Kahneman, 1998 (living in Cal.) • Sieff, Dawes & Loewenstein, 1999 (reaction to HIV status) • Wilson et al, 2000 (win or loss of team)

  4. Application to the medical domain (Which hopefully sheds light more broadly on adaptation, and the accuracy of intuitions about adaptation, in diverse domains)

  5. Most patients report a high quality of life • Brickman, Coates, and Janoff-Bulman (1978) Surprisingly small difference in self-reported happiness (on 5 point scale) between paraplegics and matched controls: • paraplegics 2.96 • controls 3.82 • Wortman and Silver (1987): quadriplegics reported no greater frequency of negative affect than control respondents! • Tyc (1992): “no difference in quality of life or psychiatric symptomatology” in young patients who had lost limbs to cancer compared with those who had not.

  6. Non-patients don’t expect patients to be as happy as they report being.. Discrepancy between patients’ evaluations of their own quality of life and non-patients’ evaluations of what their quality of life would be if they had the same health conditions Chronic dialysis (Sackett and Torrance, 1978) • Nonpatient predictions .39 • Patient reports .56 Colostomies • Nonpatient predictions .80 • Patient reports .92  The ‘discrepancy’

  7. Many possible causes of the discrepancy • Explanations that implicate non-patients • Misconstrual of medical condition? • 'Focusing illusion' • Underappreciation of adaptation • Explanations that implicate patients • Renorming of scales • Dissonance reduction • 'Neutral' explanations • Mismatch between subject populations?

  8. Whether discrepancy is important for medical policy depends on its cause • Attempts to rationalize health care delivery • Nonpatients’ evaluations of QOL serve as inputs • Informed consent/ patient decision making • Individual treatment decisions often based on perceptions, by people who do not have conditions, of what it would be like to have those conditions

  9. An illustration: • Slevin et al., 1990: % who say they'd accept a grueling course of chemotherapy for 3 extra months of life • radiotherapists 0% • oncologists 6% • healthy persons 10% • current cancer patients 42% • whose values to use?

  10. Data!

  11. Within-subject study of kidney transplant and dialysis (unpublished) (n=127 dialysis patients who ultimately received transplants; all numbers on 0-100 quality of life scale) Reported well-being pre-transplant 64.16 Predicted well-being one year later 91.19 Reported well-being one year later 76.81 Recalled well-being 47.19 Notes: - all means significantly different from one-another - those not transplanted over-predicted their own misery

  12. Evidence of misconstrual

  13. bad scales? • Classic criticism is that patients renorm the scales based on their own experiences or on new points of social comparison • But when sufferers and nonsufferers of diverse problems rated QoL with anchored or unanchored scales, anchored scales produced larger discrepancies Baron et al., “Effect of assessment method on the discrepancy between judgments of health disorders people have and do not have.”

  14. Study 2 • Conditions • Asthma • Back pain • Insomnia • Shortness • Overweight • Nearsightedness • Acne • Smoking habit • Arthritis • Heart disease • Web-based; n=99 (ages 16-68; median 36; 22% male) • Rated series of health conditions • With vague or better-defined scale • Vague – e.g., "100 is a very good quality of life" • Better-defined – e.g., "100 is as good as that of someone with a meaningful job, friends, family, and good health" • For self or other • Then stated whether they had the condition

  15. Study 2 results… • Self-ratings consistently higher than other ratings • Have/have not discrepancy was larger with better-defined scale than with vague scale

  16. Self-deception by patients? Jason Riis et al. (in progress) • Palm Pilots given to 60 end stage renal patients dialysis 3 times per week. • 28 matched (age, gender, educ., race) healthy controls • Palms carried for 7 days; beeped randomly in each 90 minute segment of day • On each beep, respondent asked 12 questions, including…

  17. Please tap the button below that best describes the mood you were feeling just before the Palm Pilot beeped: 2 … Very pleasant 1 … Slightly pleasant 0 … Neutral -1 … Slightly unpleasant -2 … Very unpleasant • When Palms returned, subjects estimated mood distributions on the above scale: • Last Week (during which they carried the palm) • Typical Week • Dialysis Scenario • Controls: (Following presentation of a dialysis scenario … "Imagine that you had dialysis") • Patients: As in the scenario; no other health problems. • Other Person (Someone else your age with same health) • Healthy • Controls: In perfect health • Patients: If never had kidney trouble

  18. Main results

  19. Conclusions so far.. • Discrepancy not due to: • mismatch between populations • scale renorming • patient misrepresentation (to self or other) • Misconstrual may contribute

  20. Mispredictions by nonpatients? • focusing illusion (Kahneman & Schkade; Wilson, Gilbert et al.) • underprediction of adaptation

  21. Tests of focusing illusion • Subjects in all studies were prospective Philadelphia jurors

  22. First defocusing task: life domains How much do you think having a below-the-knee amputation would affect: • Your overall health? • Your standard of living? • Your work? • Your love life? • Your family life? • Your social life? • Your spiritual side of your life? • Your leisure activities, such as hobbies, pastimes, travel, and entertainment?

  23. Disability Ratings Before and After Defocusing Exercise QoL Rating (0 - 100) Disability N Before AfterP Paraplegia 53 Below-knee 52 amputation 58.5 78.1 51.8 72.3 0.02 0.01

  24. Second defocusing task: concrete events If you had below the knee amputation/paraplegia, what would your experience of these things be like compared to now? • visiting with friends and/or family • paying bills and taxes • vacation and travel • getting caught in traffic • physical recreational activities • arguing with family and/or friends • reading and/or watching TV or movies • coping with death and/or illness in the family

  25. Concrete Events Defocusing: Results QoL Rating (0 - 100) Disability N Before AfterP Paraplegia 50 Paraplegia 51 BKA 51 BKA 51 55 - 71 - 51 45 72 67 .41 .05 .27 .34

  26. Third defocusing task: time weighted • “Think about the past day, starting from when you woke up yesterday to when you woke up this morning. What did you do yesterday? In the spaces provided, we would like you to list the things that took up the most amount of time from yesterday when you woke up to today when you woke up.” • Subjects were asked to imagine how these five activities would be affected if they had the disability in question.

  27. Time Weighted Defocusing Results QoL Rating (0 - 100) Disability N Before After P Paraplegia 57 Paraplegia 60 BKA 53 BKA 54 .59 .23 .60 .08 51 - 75 - 50 45 74 67

  28. Fourth Defocusing Task: Changes for Better or Worse • To get subjects to think more broadly about disabilities • We asked them to think about aspects of their live that would probably • change for the better • be unchanged • change for the worse

  29. Changes Results QoL Rating (0 - 100) Disability N BeforeAfter P Paraplegia 105 53 55 .09 Paraplegia 103 -- 57 .46 BKA 117 75 75 .31 BKA 106 -- 73 .29

  30. Are Disability Ratings Influenced by Failure to Consider Adaptation? Adaptation exercise • Think about one emotionally difficult life experience that happened to you at least 6 months prior to now • At the end of those 6 months would say you felt • Much worse • About the same • Much better than you would have predicted

  31. Adaptation Results QoL Rating (0 - 100) Disability N Before After P Paraplegia 123 Paraplegia 56 .003 .001 47 - 52 62

  32. Should we not care about environmental change (or forget about road safety)? • knowledge of these results has little effect on willingness to pay, etc.. (we may not understand why, but there may be a good reason) • happiness/quality of life matters, but doesn't include everything we care about.. • quantity and quality of well-being (Skorupski) • children • hitchhiking • mountaineering

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