Reliability and validity of an instrument for assessing patients' perceptions about medications for diabetes: the PAM-D.
ABSTRACT To evaluate the reliability and validity of the Perceptions About Medications for Diabetes (PAM-D) instrument.
The item pool was generated from a literature review and 18 focus groups of Type 2 diabetes patients. Surveys were mailed to 1,000 low-income diabetes patients; 362 were returned; 65 of 100 re-test surveys were returned.
This paper uses data from 343 Type 2 respondents. Mean age and age diagnosed were 59 and 48, respectively; 72% female; 52% African American; 51% were taking oral antihyperglycemic agents [OHA] monotherapy, 18% insulin monotherapy, and 28% insulin plus OHA. The initial 66 items were reduced to 37 across nine scales: scheduling flexibility, portability convenience, regimen inconvenience, medication effectiveness, difficulty remembering medications, gastrointestinal, hypoglycemia-related, and weight/edema physical side effects, and emotional side effects. Scale reliabilities ranged from 0.71 to 0.92 (coefficient alpha) and from 0.54 to 0.83 (test-retest coefficient, 37-81-day interval); factor loadings ranged from 0.35 to 0.86 (median, 0.67); significant scale differences across medication groups (insulin, OHA, insulin plus OHA) were consistent with a priori hypotheses.
The PAM-D has substantial reliability and validity in a low-income, inner-city population of Type 2 diabetes patients and may be valuable for understanding multidimensional perceptions driving patients' treatment preferences.
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ABSTRACT: The purpose of this qualitative study was to explore diabetes medication experiences of patients with type 2 diabetes. Study participants were recruited through newspaper advertisements and letters from primary and specialty clinics in Indianapolis, Indiana. The same professional facilitator conducted 18 focus groups (7 male, 11 female) at a Veteran Affairs facility in Indianapolis, Indiana. Participants were 138 socioeconomically diverse individuals with type 2 diabetes (68% female, 74% > or = 50 years old, 61% non-Hispanic Caucasian). Participants were on a variety of diabetes medication regimens (61% injectable insulin monotherapy or in combination with orals). Content analysis of focus group transcripts was used to establish themes. Three major themes emerged across the focus groups: (1) the inconvenience and inflexibility of the timing and frequency of administration of many diabetes treatments on participants' lives, (2) the desire to avoid injections and/or insulin therapy, and (3) the physical and emotional side effects of diabetes medications. Assuming equivalent effectiveness of 2 medications, participants would weigh the convenience and flexibility, route of administration, side effects, and cost of the medications to arrive at a treatment preference. Participants believed they currently had no opportunity to express their treatment preference to their health care provider. The best therapeutic option for a patient with type 2 diabetes will be one that is clinically effective and consistent with the patient's needs and preferences. The challenge for diabetes educators is to support patients in articulating and incorporating their needs and preferences into the treatment decision-making process.The Diabetes Educator 01/2006; 32(3):404-14. · 1.94 Impact Factor
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ABSTRACT: Diabetes is a common, debilitating chronic illness with multiple impacts. The impact on treatment satisfaction, productivity impairment and the symptom experience may be among the most important for patient-reported outcomes. This study developed and validated disease-specific, patient-reported measures for these outcomes that address limitations in currently available measures. Data was collected from the literature, experts and patients and a conceptual model of the patient-reported impact of diabetes was created. Item pools, based on the conceptual model, were then generated. The items were administered to 991 diabetes patients via a web-based survey to perform item reduction, identify relevant factor structures and assess reliability and validity following an a-priori analysis plan. All validation criteria and hypotheses were met resulting in three new, valid measures: a 21-item Satisfaction Measure (three sub-scales: burden, efficacy and symptoms), a 30-item Symptom Measure and a 14-item Productivity Measure assessing both life and work productivity impairments. This triad of measures captures important components of the multifaceted diabetes patient experience and can be considered as valid, viable options when choosing measures to assess patient-reported outcomes. Addressing these outcomes may assist researchers and clinicians to develop more patient-centered diabetes interventions and care.Quality of Life Research 05/2006; 15(3):481-91. · 2.41 Impact Factor
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ABSTRACT: The widespread use of standardized health surveys is predicated on the largely untested assumption that scales constructed from those surveys will satisfy minimum psychometric requirements across diverse population groups. Data from the Medical Outcomes Study (MOS) were used to evaluate data completeness and quality, test scaling assumptions, and estimate internal-consistency reliability for the eight scales constructed from the MOS SF-36 Health Survey. Analyses were conducted among 3,445 patients and were replicated across 24 subgroups differing in sociodemographic characteristics, diagnosis, and disease severity. For each scale, item-completion rates were high across all groups (88% to 95%), but tended to be somewhat lower among the elderly, those with less than a high school education, and those in poverty. On average, surveys were complete enough to compute scales scores for more than 96% of the sample. Across patient groups, all scales passed tests for item-internal consistency (97% passed) and item-discriminant validity (92% passed). Reliability coefficients ranged from a low of 0.65 to a high of 0.94 across scales (median = 0.85) and varied somewhat across patient subgroups. Floor effects were negligible except for the two role disability scales. Noteworthy ceiling effects were observed for both role disability scales and the social functioning scale. These findings support the use of the SF-36 survey across the diverse populations studied and identify population groups in which use of standardized health status measures may or may not be problematic.Medical Care 02/1994; 32(1):40-66. · 3.23 Impact Factor