Dataset Information

Validation of a Core Patient-Reported Outcome Measure for Fatigue in Patients Receiving Hemodialysis: The SONG-HD Fatigue Instrument.

ABSTRACT:

Background and objectives

Fatigue is a very common and debilitating symptom and identified by patients as a critically important core outcome to be included in all trials involving patients receiving hemodialysis. A valid, standardized measure for fatigue is needed to yield meaningful and relevant evidence about this outcome. This study validated a core patient-reported outcome measure for fatigue in hemodialysis.

Design, setting, participants, & measurements

A longitudinal cohort study was conducted to assess the validity and reliability of a new fatigue measure (Standardized Outcomes in Nephrology-Hemodialysis Fatigue [SONG-HD Fatigue]). Eligible and consenting patients completed the measure at three time points: baseline, a week later, and 12 days following the second time point. Cronbach α and intraclass correlation coefficient were calculated to assess internal consistency, and Spearman rho was used to assess convergent validity. Confirmatory factor analysis was also conducted. Hemodialysis units in the United Kingdom, Australia, and Romania participated in this study. Adult patients aged 18 years and over who were English speaking and receiving maintenance hemodialysis were eligible to participate. Standardized Outcomes in Nephrology-Hemodialysis, the Visual Analog Scale for fatigue, the 12-Item Short Form Survey, and Functional Assessment of Chronic Illness Therapy-Fatigue were used.

Results

In total, 485 participants completed the study across the United Kingdom, Australia, and Romania. Psychometric assessment demonstrated that Standardized Outcomes in Nephrology-Hemodialysis is internally consistent (Cronbach α =0.81-0.86) and stable over a 1-week period (intraclass correlation coefficient =0.68-0.74). The measure demonstrated convergence with Functional Assessment of Chronic Illness Therapy-Fatigue and had moderate correlations with other measures that assessed related but not the same concept (the 12-Item Short Form Survey and the Visual Analog Scale). Confirmatory factor analysis supported the one-factor model.

Conclusions

SONG-HD Fatigue seems to be a reliable and valid measure to be used in trials involving patients receiving hemodialysis.

SUBMITTER: Ju A

PROVIDER: S-EPMC7646231 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BackgroundThe objective of this research was to develop a disease-specific measure for fatigue in patients with motor neurone disease (MND) by generating data that would fit the Rasch measurement model. Fatigue was defined as reversible motor weakness and whole-body tiredness that was predominantly brought on by muscular exertion and was partially relieved by rest.MethodsQualitative interviews were undertaken to confirm the suitability of a previously identified set of 52 neurological fatigue items as relevant to patients with MND. Patients were recruited from five U.K. MND clinics. Questionnaires were administered during clinic or by post. A sub-sample of patients completed the questionnaire again after 2-4 weeks to assess test-retest validity. Exploratory factor analyses and Rasch analysis were conducted on the item set.ResultsQualitative interviews with ten MND patients confirmed the suitability of 52 previously identified neurological fatigue items as relevant to patients with MND. 298 patients consented to completing the initial questionnaire including this item set, with an additional 78 patients completing the questionnaire a second time after 4-6 weeks. Exploratory Factor Analysis identified five potential subscales that could be conceptualised as representing: 'Energy', 'Reversible muscular weakness' (shortened to 'Weakness'), 'Concentration', 'Effects of heat' and 'Rest'. Of the original five factors, two factors 'Energy' and 'Weakness' met the expectations of the Rasch model. A higher order fatigue summary scale, consisting of items from the 'Energy' and 'Weakness' subscales, was found to fit the Rasch model and have acceptable unidimensionality. The two scales and the higher order summary scale were shown to fulfil model expectations, including assumptions of unidimensionality, local independency and an absence of differential item functioning.ConclusionsThe Neurological Fatigue Index for MND (NFI-MND) is a simple, easy-to-administer fatigue scale. It consists of an 8-item fatigue summary scale in addition to separate scales for measuring fatigue experienced as reversible muscular weakness and fatigue expressed as feelings of low energy and whole body tiredness. The underlying two factor structure supports the patient concept of fatigue derived from qualitative interviews in this population. All three scales were shown to be reliable and capable of interval level measurement.

Project description:BACKGROUND:Measures that reflect patients' assessment of their health are of increasing importance as outcome measures in randomised controlled trials. The methodological approach used in the pre-validation development of new instruments (item generation, item reduction and question formatting) should be robust and transparent. The totality of the content of existing PRO instruments for a specific condition provides a valuable resource (pool of items) that can be utilised to develop new instruments. Such 'top down' approaches are common, but the explicit pre-validation methods are often poorly reported. This paper presents a systematic and generalisable 5-step pre-validation PRO instrument methodology. METHODS:The method is illustrated using the example of the Aberdeen Glaucoma Questionnaire (AGQ). The five steps are: 1) Generation of a pool of items; 2) Item de-duplication (three phases); 3) Item reduction (two phases); 4) Assessment of the remaining items' content coverage against a pre-existing theoretical framework appropriate to the objectives of the instrument and the target population (e.g. ICF); and 5) qualitative exploration of the target populations' views of the new instrument and the items it contains. RESULTS:The AGQ 'item pool' contained 725 items. Three de-duplication phases resulted in reduction of 91, 225 and 48 items respectively. The item reduction phases discarded 70 items and 208 items respectively. The draft AGQ contained 83 items with good content coverage. The qualitative exploration ('think aloud' study) resulted in removal of a further 15 items and refinement to the wording of others. The resultant draft AGQ contained 68 items. CONCLUSIONS:This study presents a novel methodology for developing a PRO instrument, based on three sources: literature reporting what is important to patient; theoretically coherent framework; and patients' experience of completing the instrument. By systematically accounting for all items dropped after the item generation phase, our method ensures that the AGQ is developed in a transparent, replicable manner and is fit for validation. We recommend this method to enhance the likelihood that new PRO instruments will be appropriate to the research context in which they are used, acceptable to research participants and likely to generate valid data.

Project description:IntroductionSustained-release intraocular implants provide a therapeutic option for open-angle glaucoma (OAG) and ocular hypertension (OHT) patients who are non-compliant with eyedrops. Currently, there are no published patient-reported outcome (PRO) measures that assess treatment satisfaction with intraocular implants. To address this gap, a new PRO instrument, the Allergan Satisfaction with Treatment Experience Questionnaire (ASTEQ), has been developed in accordance with Food and Drug Administration guidance.MethodsQualitative research interviews were conducted among patients with OAG/OHT who had received three intraocular injections of a sustained-release bimatoprost (10 or 15 µg) implant within the clinical trial setting. A preliminary conceptual framework capturing treatment satisfaction concepts in glaucoma, as identified from the literature, was used to develop a semi-structured interview guide. A concept elicitation (CE) interview to identify aspects of the glaucoma treatment experience pertinent to intraocular implants provided content for a draft instrument. A cognitive debriefing (CD) interview to test the instrument's interpretability, relevance, and validity informed its subsequent refinement. Interview analysis followed a grounded theory approach to identify data patterns and relationships.ResultsCE interviews (n = 19) indicated that participants' main considerations in rating satisfaction with implant treatment were physical comfort during preparation for the implant and implant administration, anxiety about the procedure, frequency of implant administration, possible side effects, convenience and accessibility of the implant, relationship with the clinician, and lifestyle fit. Draft ASTEQ revision based on CD interviews (n = 20) and readability tests yielded a nine-item ASTEQ instrument comprising satisfaction with overall implant experience and frequency of administration, occurrence/bother of immediate and long-term side effects, worry about implant administration and possible risks/side effects, and physical discomfort during preparation for the implant and implant administration.ConclusionThe ASTEQ instrument has demonstrated content validity in patients with OAG/OHT treated with a sustained-release bimatoprost implant. Further research is necessary to evaluate its psychometric properties.