***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: This paper outlines a model for valuing the benefits of  antenatal screening  based on the analysis of individual decision making with respect to consequent diagnostic test ing . Central to the model is the idea that the benefits of screening can be measured by valuing the improved information generated from screening . The model is developed in the context of antenatal carrier screening for cystic fibrosis ( CF ) . Benefits are as sessed by surveying women in the general population in order to establish their pref erences for two alternative methods of CF carrier screening — stepwise and couple screening . Preferences are elicited using st and ard-gamble questions in which women from a population -based r and om sample are asked to trade off risk of fetal loss with improved information from diagnostic testing . A series of st and ard-gamble questions is employed to elicit utility values for each of the possible information outcomes from screening . The expected utilities of both screening methods are calculated at both individual and group levels . The results suggest that the use of individual decision making with respect to diagnostic testing as a means of valuing the benefits of screen ing may have wide applications . Key words : benefits ; antenatal screening ; information ; st and ard gamble ; expected utility . ( Med Decis Making 1996;16:161 - 168 This paper uses best-worst scaling , a choice-based survey method , to assess adolescents ' level of concern for various adverse consequences of tobacco use . In addition to health risks cited most often ( i.e. , lung cancer and cardiovascular diseases ) , the study also focuses on less frequently mentioned health implication s ( e.g. , effects on teeth , appearance , skin , weight and sexual dysfunction ) and other adverse effects that are unrelated to health , such as cost , addiction , or manipulation by the tobacco industry . The relative importance of 15 items was assessed in a sample of 376 adolescents ( ages 14 - 19 years ) in Western Switzerl and . The result ing data provide rich information on the relative importance of the items considered and even allow for the assessment of individual-level preference scales . The results indicate that apart from lung cancer that is consistently rated as being of most concern , less-mentioned health risks such as reduced physical capacity and sexual dysfunction are of significant importance . Subgroup analyses and results from a r and om parameter approach highlight substantial heterogeneity in preferences that should be exploited in future prevention messages Background This study was undertaken to estimate utility values for alternative treatment intervals for long acting antipsychotic intramuscular injections for the treatment of schizophrenia . Methods Vignettes were developed using the published literature and an iterative consultation process with expert clinicians and patient representative groups . Four vignettes were developed . The first was a vignette of relapsed/untreated schizophrenia . The other three vignettes presented a st and ardised picture of well-managed schizophrenia with variations in the intervals between injections : once every 2-weeks , 4-weeks and 3-months . A st and ardised time trade off ( TTO ) approach was used to obtain utility values for the vignettes . As a societal perspective was sought , a representative sample of individuals from across the community ( Sydney , Australia ) was recruited . Ninety-eight people completed the TTO interview . The vignettes were presented in r and om order to prevent possible ordering effects . Results A clear pattern of increasing utility was observed with increasing time between injections . Untreated schizophrenia was rated as very poor health-related quality of life with a mean ( median ) utility of 0.27 ( 0.20 ) . The treated health states were rated at much higher utilities and were statistically significantly different ( p < 0.001 ) from each other : ( 1 ) 2-weekly : mean ( median ) utility = 0.61 ( 0.65 ) ; ( 2 ) 4-weekly : mean ( median ) utility = 0.65 ( 0.70 ) ; ( 3 ) 3-monthly : mean ( median ) utility = 0.70 ( 0.75 ) . Conclusions This study has provided robust data indicating that approximately a 0.05 utility difference exists between treatment options , with the highest utility assigned to 3-monthly injections The techniques of cost utility analysis ( CUA ) were used to evaluate the treatment of gallstone disease by open and laparoscopic cholecystectomy and by extracorporeal shockwave lithotripsy ( ESWL ) .  The application of the techniques in this context raised three method ological questions which are not satisfactorily resolved in the literature . The first is whether an ex ante or ex post perspective is best adopted for the measurement of quality of life ( QoL ) . The second is the method for converting a short term deterioration in QoL followed by full health into QALYs and the reliability of the methods available . The third is the issue of indirect costs which , in the context of a temporary disease state , can not be easily avoided . The economic evaluation found laparoscopic cholecystectomy to be generally superior than the competitor technologies ( entailing lower costs and better outcomes ) . However , the results were sensitive to assumptions about the perspective for measuring benefits and the inclusion of indirect costs OBJECTIVES To estimate the health and non-health effects of fluoridation on well-being using the willingness-to-pay technique . METHODS A pilot study of 100 people was undertaken in which the willingness-to-pay technique was used to estimate the welfare effects of  community water fluoridation in the city of Sheffield , in the United Kingdom . In view of the pilot nature of the study , it was decided to use quota sampling based on age and sex rather than r and om sampling . Reasons for respondents ' answers and their previous knowledge of fluoridation were also noted . RESULTS Sixty-two percent of respondents were in favour of fluoridation , 31 % were opposed , and 7 % were unsure . Thirty-one respondents refused to answer the willingness-to-pay questions . The mean willingness to pay for those in favour of fluoridation was less than that for those opposed to fluoridation . The main reasons given for opposing fluoridation were its impact on freedom of choice and the desire for pure water . Nineteen percent of the sample held incorrect information on the effects of fluoridation . CONCLUSIONS The study illustrates how a simple referendum can miss important information regarding the intensity of individuals ' preferences . An important aspect of the willingness-to-pay technique is its ability to identify ' losers ' and quantify their welfare loss . This issue has been ignored by all previous economic evaluations of fluoridation . Further investigation is required to replicate this work on a larger sample of individuals , and to develop the willingness-to-pay technique Aims : To investigate the relationship between the framing of survival gains and the perceived value of cancer care . Methods : Through a population -based survey of 2040 US adults , respondents were r and omized to one of the two sets of hypothetical scenarios , each of which described the survival benefit for a new treatment as either an increase in median survival time ( median survival ) , or an increase in the probability of survival for a given length of time ( l and mark survival ) . Each respondent was presented with two r and omly selected scenarios with different prognosis and survival improvements , and asked about their willingness to pay ( WTP ) for the new treatments . Results : Predicted WTP increased with survival benefits and respondents ’ income , regardless of how survival benefits were described . Framing therapeutic benefits as improvements in l and mark rather than median time survival increased the proportion of the population willing to pay for that gain by 11–35 % , and the mean WTP amount by 42–72 % in the scenarios we compared . Conclusion : How survival benefits are described may influence the value people place on cancer care Background . In the Netherl and s , in low-risk pregnancies , the views of pregnant women and their partners on characteristics of obstetric care services are leading for the selection of place of birth . The aim of this study was to investigate whether there are differences between the decision-making process of pregnant women and their partners with regard to these attributes of obstetric care . Methods . This study was a prospect i ve cohort study with low-risk nulliparae and their partners . A question naire , based on the method of discrete-choice experiment , was used to gather the data . Results . Possibility of influencing decision-making was , both for pregnant women ( n = 321 ) and their partners ( n = 212 ) , the most important characteristic of the obstetric care . For women , a home-like birth setting was an important characteristic , while the partners found the possibility on pain-relief treatment during birth important . Conclusions . The results of this study suggest that women and their partners have clearly defined preferences for obstetric care . There are also some essential differences between the preferences of these two groups . The findings are important where policy issues related to aspects of maternity care service delivery are being considered Background In clinical trials , patients have expressed greater satisfaction with inhaled human insulin ( EXUBERA ® , Pfizer ) than with injectable insulin . No studies to date have attempted to quantify the strength of preferences for these alternative routes of administration . Objective To elicit health state preference values from people with diabetes mellitus for treatment with inhaled human insulin compared with injectable insulin . Study design A patient preference study . Methods Written descriptions were developed for five clinical scenarios : two for type 1 diabetes and three for type 2 diabetes . Each scenario required adjustment or initiation of insulin treatment because of poor glycaemic control . Two alternative insulin regimens were described for each scenario : injectable-only or inhaled human insulin to replace or reduce the number of daily injections . Equal efficacy was assumed within each of these scenario pairs . A total of 344 UK adults ( 66 % male ) , 132 ( mean age 49 years ) with type 1 diabetes and 212 ( mean age 63 years ) with type 2 diabetes , rated scenario pairs corresponding to their own type of diabetes and rated their own health by time trade-off ( TTO ) , by correspondence with EQ-5D health descriptions and on the EQ-5D visual analogue scale . Respondents stated their preference for , or indifference between , the injection-only or inhalation variant comprising each scenario pair . TTO utilities and EQ-5D utilities by UK community tariff were compared within each scenario pair , for the total sample rating , each scenario pair , and by subgroups of stated preference for each variant . Results A majority , ranging from 63 % to 81 % across the scenarios , preferred inhalation . Mean differences in TTO scores were 0.074 , 0.076 , 0.088 , 0.053 and 0.043 for the five scenarios , respectively ( p < 0.005 for all ) . Mean EQ-5D differences were 0.043 , 0.029 , 0.037 , 0.020 and 0.021 for the five scenarios , respectively ( p < 0.05 for scenarios 1 and 3 ) , driven mainly by differences on the pain/discomfort dimension of the EQ-5D . Differences in favour of inhalation among those preferring inhalation , were greater than differences in favour of injections among those preferring injections . Mean self-rated health was similar between respondents with type 1 and type 2 diabetes , at 0.83 ( TTO ) and 0.75 ( EQ-5D ) . The TTO was more sensitive than EQ-5D . Self-rated health by EQ-5D compared closely with reported values from the UK Prospect i ve Diabetes Study ( UKPDS ) . Conclusions This study highlights the utility differences that people with diabetes perceive between the prospect of inhaled and injected routes of insulin administration , even under the assumption of no difference in efficacy . These differences are magnified when the comparison in utility scores is between the majority who prefer the inhaled route and the minority who prefer the injectable route OBJECTIVE To examine preferences for  HIV test methods  using conjoint analysis , a method used to measure economic preferences ( utilities ) . DATA SOURCES  Self-administered surveys at four publicly funded HIV testing locations in San Francisco , California , between November 1999 and February 2000 ( n = 365 , 96 percent response rate ) . STUDY DESIGN We defined six important attributes of  HIV tests and their levels ( location , price , ease of collection , timeliness/accuracy , privacy/anonymity , and counseling ) . A fractional factorial design was used to develop scenarios that consisted of combinations of attribute levels . Respondents were asked 11 questions about whether they would choose " Test A or B " based on these scenarios . DATA ANALYSIS We used r and om effects probit models to estimate utilities for testing attributes . Since price was included as an attribute , we were able to estimate willingness to pay , which provides a st and ardized measure for use in economic evaluations . We used extensive analyses to examine the reliability and validity of the results , including analyses of : ( 1 ) preference consistency , ( 2 ) willingness to trade among attributes , and ( 3 ) consistency with theoretical predictions . PRINCIPAL FINDINGS Respondents most preferred tests that were accurate/timely and private/anonymous , whereas they had relatively lower preferences for in-person counseling . Respondents were willing to pay an additional $ 35 for immediate , highly accurate results ; however , they had a strong disutility for receiving immediate but less accurate results . By using conjoint analysis to analyze new combinations of attributes , we found that respondents would most prefer instant , highly accurate home tests , even though they are not currently available in the U.S. Respondents were willing to pay $ 39 for a highly accurate , instant home test . CONCLUSIONS The method of conjoint analysis enabled us to estimate utilities for specific attributes of HIV tests as well as the overall utility obtained from various HIV tests , including tests that are under consideration but not yet available . Conjoint analysis offers an approach that can be useful for measuring and underst and ing the value of other health care goods , services , and interventions This paper is concerned with the concept of process  utility  in health care . The paper begins by outlining the reasons why it might be important to include process utility in health care evaluation . Problems in defining process and outcome are then outlined , after which the discussion turns to how process utility might be detected empirically . Willingness to pay ( 
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Conclusions Evidence from the literature shows variability in how meta-health effects are being measured for use in economic evaluations .