Measurement properties of the Flu-Like Symptom Index from the Hepatitis Physical Symptom Severity Diary

Purpose Chronic Hepatitis C (CHC) Virus infection is a serious health issue in the US. Standard treatment involves peginterferon alpha and ribavirin, often associated with adverse side effects including flu-like symptoms. These adverse effects are common reasons for the discontinuation of treatment and therefore represent a major obstacle in the effective treatment of CHC. Methods The Hepatitis Physical Symptom Severity Diary, a newly developed patient-reported outcome mea-sure for assessing physical symptoms in CHC patients, was recently developed. It contains four questions addressing flu-like symptoms [the Flu-Like Symptom Index (FLSI)]. Measurement properties of the FLSI in CHC patients were assessed using data from two randomized clinical trials. Results Exploratory factor analysis using data from baseline and the last visit while on treatment supported a single-factor solution for the FLSI. Internal reliability and test–retest reliability are acceptable (Cronbach’s alpha range 0.73–0.81; intraclass correlation coefficient range 0.85–0.97), and correspondence to several similar con-structs was acceptable. The FLSI score was higher among those with investigator-reported flu-like symptoms (mean = 4.1) versus those without (1.4), although not statistically significant (p = 0.12). Responsiveness of the FLSI was moderate, as measured by standardized effect sizes and response means, and the minimum important difference (MID) was estimated at 2.5–3.0 points. Conclusions While additional research should be con-ducted to evaluate validity with more closely related con-structs and to utilize anchor-based methods for estimating the MID, data suggest that the FLSI has acceptable mea-surement properties and can be an effective tool in assessing flu-like symptoms in CHC patients

Estimating the clinical effectiveness and value-based price range of erenumab for the prevention of migraine in patients with prior treatment failures: a US societal perspective

BACKGROUND: Frequent migraine with four or more headache days per month is a common, disabling neurovascular disease. From a US societal perspective, this analysis models the clinical efficacy and estimates the value-based price (VBP) for erenumab, a fully human monoclonal antibody that inhibits the calcitonin gene-related peptide receptor. METHODS: A Markov health state transition model was developed to estimate the incremental costs, quality-adjusted life-years (QALYs), and value-based price range for erenumab in migraine prevention. The model comprises "on preventive treatment", "off preventive treatment", and "death" health states across a 10-year time horizon. The evaluation compared erenumab to no preventive treatment in episodic and chronic migraine patients that have failed at least one preventive therapy. Therapeutic benefits are based on estimated changes in monthly migraine days (MMD) from erenumab pivotal clinical trials and a network meta-analysis of migraine studies. Utilities were estimated using previously published mapping algorithms. A VBP analysis was performed to identify maximum erenumab annual prices at willingness-to-pay (WTP) thresholds of $100,000-$200,000 per QALY. Estimates of VBP under different scenarios such as choice of different comparators, assumptions around inclusion of placebo effect, and exclusion of work productivity losses were also generated. RESULTS: Erenumab resulted in incremental QALYs of 0.185 vs supportive care (SC) and estimated cost offsets due to reduced MMD of $8,482 over 10 years, with an average duration of treatment of 2.01 years. The estimated VBP at WTP thresholds of$100,000-$200,000 for erenumab compared to SC ranged from$14,238-$23,998. VBP estimates including the placebo effect and excluding work productivity ranged from$7,445-$13,809; increasing to$12,151-$18,589 with onabotulinumtoxinA as a comparator in chronic migraine. CONCLUSION: Erenumab is predicted to reduce migraine-related direct and indirect costs, and increase QALYs compared to SC

Health state utilities associated with attributes of treatments for hepatitis C

BACKGROUND: Cost-utility analyses are frequently conducted to compare treatments for hepatitis C, which are often associated with complex regimens and serious adverse events. Thus, the purpose of this study was to estimate the utility associated with treatment administration and adverse events of hepatitis C treatments. DESIGN: Health states were drafted based on literature review and clinician interviews. General population participants in the UK valued the health states in time trade-off (TTO) interviews with 10- and 1-year time horizons. The 14 health states described hepatitis C with variations in treatment regimen and adverse events. RESULTS: A total of 182 participants completed interviews (50 % female; mean age = 39.3 years). Utilities for health states describing treatment regimens without injections ranged from 0.80 (1 tablet) to 0.79 (7 tablets). Utilities for health states describing oral plus injectable regimens were 0.77 (7 tablets), 0.75 (12 tablets), and 0.71 (18 tablets). Addition of a weekly injection had a disutility of −0.02. A requirement to take medication with fatty food had a disutility of −0.04. Adverse events were associated with substantial disutilities: mild anemia, −0.12; severe anemia, −0.32; flu-like symptoms, −0.21; mild rash, −0.13; severe rash, −0.48; depression, −0.47. One-year TTO scores were similar to these 10-year values. CONCLUSIONS: Adverse events and greater treatment regimen complexity were associated with lower utility scores, suggesting a perceived decrease in quality of life beyond the impact of hepatitis C. The resulting utilities may be used in models estimating and comparing the value of treatments for hepatitis C. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10198-014-0649-6) contains supplementary material, which is available to authorized users

Migraine day frequency in migraine prevention: longitudinal modelling approaches

Background Health economic models are critical tools to inform reimbursement agencies on health care interventions. Many clinical trials report outcomes using the frequency of an event over a set period of time, for example, the primary efficacy outcome in most clinical trials of migraine prevention is mean change in the frequency of migraine days (MDs) per 28 days (monthly MDs [MMD]) relative to baseline for active treatment versus placebo. Using these cohort-level endpoints in economic models, accounting for variation among patients is challenging. In this analysis, parametric models of change in MMD for migraine preventives were assessed using data from erenumab clinical studies. Methods MMD observations from the double-blind phases of two studies of erenumab were used: one in episodic migraine (EM) (NCT02456740) and one in chronic migraine (CM) (NCT02066415). For each trial, two longitudinal regression models were fitted: negative binomial and beta binomial. For a thorough comparison we also present the fitting from the standard multilevel Poisson and the zero inflated negative binomial. Results Using the erenumab study data, both the negative binomial and beta-binomial models provided unbiased estimates relative to observed trial data with well-fitting distribution at various time points. Conclusions This proposed methodology, which has not been previously applied in migraine, has shown that these models may be suitable for estimating MMD frequency. Modelling MMD using negative binomial and beta-binomial distributions can be advantageous because these models can capture intra- and inter-patient variability so that trial observations can be modelled parametrically for the purposes of economic evaluation of migraine prevention. Such models have implications for use in a wide range of disease areas when assessing repeated measured utility values

Development and exploration of the content validity of a patient-reported outcome measure to evaluate the impact of migraine- the migraine physical function impact diary (MPFID)

Abstract Background Adults with migraine experience substantial reductions in quality of life during and in-between migraine attacks. Clinical and regulatory guidelines encourage the inclusion of patient reported outcomes for the evaluation of benefits of interventions for migraine. Methods The conceptual framework and items for a new patient-reported outcome (PRO) instrument, the Migraine Physical Function Impact Diary (MPFID), were developed using scientific methods recommended to ensure content validity of PRO instruments. The MPFID was developed to measure the impact of migraine on physical functioning based on themes raised in concept elicitation (CE) interviews (conducted previously) with adults with migraine. Cognitive interviews were conducted with adults with migraine to further explore content validity. The instrument was modified following an interim analysis of a first round of cognitive interviews, to assess comprehensiveness and clarity of items, instructions, and response options. Refinements were subsequently tested in additional cognitive interviews. Results The conceptual framework included impacts on physical functioning experienced by most adults with migraine and deemed clinically relevant for measuring the outcome of an intervention for migraine. Concepts in the framework included the impact of migraine on physical impairments (acts) and ability to complete day-to-day activities and perform everyday activities (tasks). MPFID items were generated to evaluate functioning over the past 24 h and to collect data daily, to capture experiences on days with migraine as well as the days in-between migraines. Items asked about needing to rest or lie down; ability to get out of bed, stand up, bend over, walk, perform household chores, do tasks outside the home, keep routines or schedules, get ready for the day, do activities that require concentration or clear thinking; difficulty moving head and body, doing activities requiring physical effort; avoiding interacting with others. Initial modifications based on the first round of cognitive interviews (n = 8) included clarifying instructions, updating three items to enhance specificity and clarity, and revising one item to include gender-neutral language. The second round of interviews (n = 9) confirmed acceptability of revisions and supported content validity. Conclusions The results provide qualitative evidence supporting the content validity of the MPFID for evaluating outcomes of interventions for migraine

Additional file 1: Table S1. of Development and exploration of the content validity of a patient-reported outcome measure to evaluate the impact of migraine- the migraine physical function impact diary (MPFID)

Inclusion and Exclusion Criteria for Cognitive Interview Study. (DOCX 27 kb