Biomedical subjects
S S Sen
Publications and source records attributed to S S Sen.
Vitamin D inadequacy among post-menopausal women: a systematic review.
BACKGROUND: Vitamin D inadequacy has been studied extensively, due to concerns about ageing populations, associations with osteoporosis and other disorders (including non-musculoskeletal), and high prevalence. AIM: To review recent reports on the prevalence of vitamin D inadequacy among post-menopausal women with and without osteoporosis and/or other musculoskeletal diseases. DESIGN: Systematic review. METHODS: We reviewed publications in the past 10 years reporting prevalence estimates for vitamin D inadequacy, reported as serum 25(OH)D values below various levels. Thirty published studies in the English language were identified, from January 1994 through April 2004. RESULTS: In osteoporotic populations, the prevalence of 25(OH) vitamin D concentration <12 ng/ml ranged from 12.5% to 76%, while prevalence rates reached 50% to 70% of patients with a history of fracture(s) using a cut-off of 15 ng/ml. In post-menopausal women, the prevalence of 25(OH) vitamin D concentrations <or=20 ng/ml ranged from 1.6% to 86% for community-living and institutionalized women, respectively. The most common factors associated with inadequate vitamin D levels included limited sun exposure, lack of dietary vitamin D intake, nursing home environment, wintertime, and increasing age (over 70 years). DISCUSSION: The prevalence of inadequate vitamin D levels appears to be high in post-menopausal women, especially in those with osteoporosis and history of fracture. Vitamin D supplementation in this group might offer scope for prevention of falls and fracture, especially in elderly and osteoporotic populations.
Validation and comparative evaluation of the osteoporosis self-assessment tool (OST) in a Caucasian population from Belgium.
BACKGROUND: Risk indices have been developed to identify women at risk of low bone mineral density (BMD) who should undergo BMD testing. AIM: To compare the performance of four risk indices in White ambulatory women in Belgium. DESIGN: Epidemiological cross-sectional study. METHODS: Records were analysed for 4035 postmenopausal White women without Paget's disease or advanced osteoarthritis, seen at an out-patient osteoporosis centre between January 1996 and September 1999. Osteoporosis risk index scores were compared to bone density T-scores. The ability of each risk index to identify women with low BMD (T-score < -2.0) or osteoporosis (T < -2.5) was evaluated. RESULTS: Using an Osteoporosis Self-Assessment Tool (OST) score <2 to recommend DXA referral, sensitivity ranged from 85% at the lumbar spine to 97% at the total hip to detect BMD T-scores of <or= -2.5, and specificity ranged from 34% at the total hip to 37% at the femoral neck and lumbar spine. The negative predictive value was high at all skeletal sites (89-99%), demonstrating the usefulness of the OST to identify patients who have normal BMD and should not receive DXA testing. All risk indices performed similarly, although the OST had somewhat better sensitivity and somewhat lower specificity than the other indices at the cut-offs evaluated. Among the 11-12% of women who were classified as highest risk using OST or the Osteoporosis Index of Risk (OSIRIS), 81-85% had low bone mass and 68-74% had osteoporosis. DISCUSSION: The performance of these risk indices among women in Belgium was similar to that reported earlier for other samples in Asian countries, the US, and the Netherlands. The OST and other risk indices are effective and efficient tools to help target high-risk women for DXA testing.
Assessment of a patient-based pharmaceutical care scale.
The Purdue Pharmacist Directive Guidance scale (PPDG), which is designed to measure patients' perceptions of the level of directive guidance received from pharmacists, was studied. Hypertension patients were interviewed by telephone between July 15 and August 15, 1998, with a survey including the PPDG, the Medication Adherence Scale (MAS), and the Friends and Family Support scale (FFS). The Behavioral Pharmaceutical Care Scale (BPCS) was mailed between May 15 and July 15, 1998, to pharmacies from which the patients obtained most of their prescriptions. The MAS measures patients' medication adherence, and the FFS measures their perceptions of the social support they receive from family and friends. Analysis of variance was used to assess whether there was significant variation in scale scores across pharmacies. Pearson correlation analysis was used to assess simple correlation among scales, and regression analysis was used to examine the association between scale scores while controlling for demographic variables, family support, and number of prescription drugs taken. Interviews with 163 patients were analyzed, and 64 pharmacists representing 32 pharmacies responded. The PPDG did not detect any difference across pharmacies in patients' perceptions of the level of directive guidance received. There was no significant correlation between PPDG scores and pharmacists' perceptions of the level of pharmaceutical care provided as measured with the BPCS or between PPDG scores and MAS scores. The findings reconfirmed the PPDG's reliability and factor structure and provided some evidence of convergent validity. The PPDG was reliable. Evidence of validity was not conclusive, although the high threshold for validity may have been responsible for this.
Selecting among health-related quality-of-life instruments.
A method of evaluating health-related quality-of-life (HRQL) instruments is described. Selection of an HRQL instrument should be based on the intended purpose and how well the instrument satisfies that purpose. An available methodological framework for developing HRQL instruments can be used; its premise is that the developmental process and psychometric properties of an instrument vary with the intended purpose. Intended purposes are classified as evaluative, discriminative, and predictive. Developmental steps are selection of items, item scaling, item reduction and assessment of internal consistency, and determination of reliability, validity, and responsiveness. Specific criteria apply to each step. An evaluation of asthma-specific HRQL instruments demonstrates use of the method. A useful method exists for selecting among available HRQL instruments on the basis of the instruments' intended purposes.