New therapies for treating Down syndrome require quality of life measurement.

Down syndrome (DS) is the most common genetic cause of cognitive deficits. Using mouse models and therapies for Alzheimer disease, researchers are exploring therapies that may improve cognitive function in people with DS. These developments shift the health economic paradigm of understanding DS from determining the appropriate screening tool to the effect of therapy on quality of life in those with DS. To date, there are no validated quality of life instruments for DS. Research should begin to develop instruments that can evaluate changes in quality of life in therapeutic trials and beyond.

Assessing adherence-based quality measures in epilepsy.

OBJECTIVE: To examine the relationship of three alternative measures of adherence with seven negative outcomes associated with epilepsy for development of a quality measure in epilepsy. DESIGN: Retrospective cohort analysis. SETTING: PharMetrics national claims database. PARTICIPANTS: Patients in the PharMetrics database for the years 2004-08 taking antiepileptic drugs. INTERVENTION: None. MAIN OUTCOME MEASURES: For each definition of adherence, the odds ratios (ORs) comparing non-adherent with adherent groups were assessed for consistency and direction for the number of hospital admissions, emergency room (ER) visits, head injuries including traumatic brain injuries, falls, motor vehicle accidents (MVAs), fractures and a 'seizure' outcome defined as hospital admissions or ER visits with a primary diagnosis of epilepsy or convulsions. RESULTS: The inclusion criteria were met by 31 635 individuals. In the multivariate analysis, the adherent group had lower odds of hospital admissions with ORs for the eight specifications ranging from 0.729 to 0.872 and ER visits where ORs for the eight specifications ranged from 0.750 to 0.893. The eight ORs for head injuries ranged from 0.647 to 0.888. For fractures, the ORs ranged from 0.407 to 0.841. Our proxy for seizure was inconsistently associated with adherence status. CONCLUSIONS: All the adherence measures defined non-adherent groups that were associated with negative outcomes in epilepsy.

Are Laboratory Parameter (Biomarker) Values Similar to the Healthy Volunteer Reference Range in Individuals with Diabetes.

BACKGROUND: Identification of laboratory parameter clinical safety signals depends on the terminology and scoring criteria. Grade 1 scoring criteria in the Common Terminology Criteria for Adverse Events (CTCAE) is typically based on the healthy volunteer reference range (HVRR). The objectives of this study were to determine 1) what laboratory parameters in individuals with diabetes are potentially different from the HVRR and 2) what fold change from baseline should be expected in this population. MATERIALS AND METHODS: Baseline data from the individuals with diabetes clinical trial data (TransCelerate dataset) were compared to the HVRR using a 10% threshold above HVRR to classify laboratory parameters as potentially different from the HVRR. These parameters were then evaluated longitudinally to determine the expected x-baseline values for individuals with diabetes for potential use in identifying drug-induced changes. RESULTS: The baseline data determined that 28% of the laboratory parameters evaluated were potentially different from the HVRR. Longitudinal data analysis determined 1) thresholds for 13 of these laboratory parameters with the subjects above the threshold having greater variability than those below the threshold, and 2) the expected upper limits (x-baseline) were calculated for the laboratory parameters. For example, a 1.8-2.6 x-baseline value for alanine aminotransferase, depending on how the baseline is calculated, is expected in individuals with diabetes. CONCLUSION: It is not uncommon for laboratory parameters in individuals with diabetes clinical trials to be potentially different from the HVRR, and the x-baseline criteria for 13 of these laboratory biomarkers was determined for this population. This suggests consideration in modifying the current CTCAE grade 1 criteria of >1.5-3.0 x-baseline should be further investigated as to if the current criteria detects too many false-positive signals in this population.

Bioterrorism surveillance and privacy: intersection of HIPAA, the Common Rule, and public health law.

The threat of bioterrorism in the wake of the September 11, 2001, terrorist attacks cannot be ignored. Syndromic surveillance, the practice of electronically monitoring and reporting real-time medical data to proactively identify unusual disease patterns, highlights the conflict between safeguarding public health while protecting individual privacy. Both the Health Insurance Portability and Accountability Act and the Common Rule (which promulgates protections for individuals in federally sponsored medical research programs) safeguard individuals. Public health law protects the entire populace; uneven state-level implementation lacks adequate privacy protections. We propose 3 models for a nationwide bioterrorism surveillance review process: a nationally coordinated systems approach to using protected health information, creating public health information privacy boards, expanding institutional review boards, or some combination of these.

Are laboratory parameter (biomarker) values similar to the healthy volunteer reference range in all patient populations?

BACKGROUND: Liver biomarkers alanine aminotransferase (ALT) and bilirubin in patients with hepatitis are above the healthy volunteer reference range (HVRR) at baseline (prior to receiving the clinical trial medication). Discussions continue as how to best distinguish drug-induced liver injury in patients with abnormal baseline values participating in clinical trials. This study investigated if other baseline routine clinical safety biomarkers (lab parameters) are different from the HVRR. MATERIALS AND METHODS: Clinical trial data (TransCelerate dataset) from placebo and standard of care treated patients were compared to the HVRR using a 10% threshold above or below the HVRR to classify a lab parameter in a patient population as potentially different from the HVRR at baseline. The TransCelerate dataset, batch 4, contained data from patients with Alzheimer's, asthma, COPD, cardiovascular disease, diabetes, hidradenitis, hypercholesterolemia, rheumatoid arthritis, schizophrenia, stroke, and ulcerative colitis. A subset of the 200 biomarkers in Trans-Celerate were evaluated in this pilot: glucose, platelet count, neutrophil count, ALT, aspartate aminotransferase (AST), and bilirubin. RESULTS: Glucose was potentially higher than the HVRR in patients with diabetes, COPD, cardiovascular disease, hypercholesterolemia, and schizophrenia. At least one or more of the hematology and hepatic biomarkers were different from the HVRR in at least one patient population, except bilirubin. All the patient populations, except Alzheimer's and asthma, had at least one biomarker that was higher than the HVRR. SUMMARY: The routine biomarkers evaluated in this pilot study demonstrated that not all lab parameters in patient populations are similar to the HVRR. Further efforts are needed to determine which biomarkers are different from the HVRR and how to evaluate the biomarkers in patient populations for detecting drug-induced altered lab values in clinical trials.

Repeated tobacco-use screening and intervention in clinical practice: health impact and cost effectiveness.

BACKGROUND: This report updates 2001 estimates of disease burden prevented and cost effectiveness of tobacco-use screening and brief intervention relative to that of other clinical preventive services. It also addresses repeated counseling because the literature has focused on single episodes of treatment, while in reality that is neither desirable nor likely. METHODS: Literature searches led to four models for calculating the clinically preventable burden of deaths and morbidity from smoking as well as the cost effectiveness of providing the service annually over time. The same methods were used in similar calculations for other preventive services to facilitate comparison. RESULTS: Using methods consistent with existing literature for this service, an estimated 190,000 undiscounted quality-adjusted life years (QALYs) are saved at a cost of $1100 per QALY saved (discounted). These estimates exclude financial savings from smoking-attributable disease prevented and use the average 12-month quit rate in clinical practice for tobacco screening and brief cessation counseling with cessation medications (5.0%) and without (2.4%). Including the savings of prevented smoking-attributable disease and using the effectiveness of repeated interventions over the lifetime of smokers (23.1%), 2.47 million QALYs are saved at a cost savings of $500 per smoker who receives the service. CONCLUSIONS: This analysis makes repeated clinical tobacco-cessation counseling one of the three most important and cost-effective preventive services that can be provided in medical practice. Greater efforts are needed to achieve more of this potential value by increasing current low levels of performance.

Influenza vaccination health impact and cost effectiveness among adults aged 50 to 64 and 65 and older.

BACKGROUND: Influenza causes approximately 36,000 deaths per year in the United States despite the presence of an effective vaccine. This assessment of the value of influenza vaccination to the U.S. population is part of an update to the 2001 ranking of clinical preventive services recommended by the U.S. Preventive Services Task Force. The forthcoming ranking will include the new recommendation of the Advisory Committee on Immunization Practices to extend influenza vaccination to adults aged 50 to 64 years. METHODS: This service is evaluated on the two most important dimensions: burden of disease prevented and cost effectiveness. Study methods, described in a companion article, are designed to ensure consistency across many services. RESULTS: Over the lifetime of a birth cohort of 4 million, it is estimated that about 275,000 quality-adjusted life years (QALYs) would be saved if influenza vaccination were offered annually to all people after age 50. Eighty percent of the QALYs saved (220,000) would be achieved by offering the vaccine only to persons aged 65 and older. In year 2000 dollars, the cost effectiveness of influenza vaccination is $980 per QALY saved in persons aged 65 and older, and $28,000 per QALY saved in persons aged 50 to 64. When the costs of patient time and travel are excluded, the cost effectiveness ratio of vaccinating 50- to 64-year-olds decreases to $7200 per QALY saved, and vaccinating those aged 65 and older saves $17 per person vaccinated. CONCLUSIONS: Influenza vaccination is a high-impact, cost-effective service for persons aged 65 and older. Vaccinations are also cost effective for persons aged 50 to 64.

Colorectal cancer screening: health impact and cost effectiveness.

BACKGROUND: Colorectal cancer is the second leading cause of cancer-related death in the United States, yet recommended screenings are not delivered to most people. This assessment of colorectal cancer screening's value to the U.S. population is part of the update to a 2001 ranking of recommended clinical preventive services found in the accompanying article. This article describes the burden of disease prevented and cost-effectiveness as a result of offering patients a choice of colorectal cancer screening tools. METHODS: Methods used were designed to ensure consistent estimates across many services and are described in more detail in the companion articles. In a secondary analysis, the authors also estimated the impact of increasing offers for colorectal cancer screening above current levels among the current cross-section of adults aged 50 and older. RESULTS: If a birth cohort of 4 million were offered screening at recommended intervals, 31,500 deaths would be prevented and 338,000 years of life would be gained over the lifetime of the birth cohort. In the current cross-section of people aged 50 and older, 18,800 deaths could be prevented each year by offering all people in this group screening at recommended intervals. Only 58% of these deaths are currently being prevented. In year 2000 dollars, the cost effectiveness of offering patients aged 50 and older a choice of colorectal cancer screening options is $11,900 per year of life gained. CONCLUSIONS: Colorectal cancer screening is a high-impact, cost-effective service used by less than half of persons aged 50 and older.

Priorities among effective clinical preventive services: results of a systematic review and analysis.

BACKGROUND: Decision makers at multiple levels need information about which clinical preventive services matter the most so that they can prioritize their actions. This study was designed to produce comparable estimates of relative health impact and cost effectiveness for services considered effective by the U.S. Preventive Services Task Force and Advisory Committee on Immunization Practices. METHODS: The National Commission on Prevention Priorities (NCPP) guided this update to a 2001 ranking of clinical preventive services. The NCPP used new preventive service recommendations up to December 2004, improved methods, and more complete and recent data and evidence. Each service received 1 to 5 points on each of two measures--clinically preventable burden and cost effectiveness--for a total score ranging from 2 to 10. Priorities for improving delivery rates were established by comparing the ranking with what is known of current delivery rates nationally. RESULTS: The three highest-ranking services each with a total score of 10 are discussing aspirin use with high-risk adults, immunizing children, and tobacco-use screening and brief intervention. High-ranking services (scores of 6 and above) with data indicating low current utilization rates (around 50% or lower) include: tobacco-use screening and brief intervention, screening adults aged 50 and older for colorectal cancer, immunizing adults aged 65 and older against pneumococcal disease, and screening young women for Chlamydia. CONCLUSION: This study identifies the most valuable clinical preventive services that can be offered in medical practice and should help decision-makers select which services to emphasize.

Priorities among effective clinical preventive services: methods.

Decision makers want to know which healthcare services matter the most, but there are no well-established, practical methods for providing evidence-based answers to such questions. Led by the National Commission on Prevention Priorities, the authors update the methods for determining the relative health impact and economic value of clinical preventive services. Using new studies, new preventive service recommendations, and improved methods, the authors present a new ranking of clinical preventive services in the companion article. The original ranking and methods were published in this journal in 2001. The current methods report focuses on evidence collection for a priority setting exercise, guidance for which is effectively lacking in the literature. The authors describe their own standards for searching, tracking, and abstracting literature for priority setting. The authors also summarize their methods for making valid comparisons across different services. This report should be useful to those who want to understand additional detail about how the ranking was developed or who want to adapt the methods for their own purposes.

Creating standard cost measures across integrated health care delivery systems.

BACKGROUND: Economic analyses are increasingly important in medical research. Accuracy often requires that they include large, diverse populations, which requires data from multiple sources. The difficulty is in making the data comparable across different settings. This article focuses on how to create comparable measures of health care resource use and cost using data from seven health plans and delivery systems participating in the Cancer Research Network's HMOs Investigating Tobacco study. METHODS: We used a data inventory to identify variation in data capture across sites and used data dictionaries to develop algorithms for assigning standardized cost to the three major components of health care use: outpatient, inpatient, and pharmacy. RESULTS: The plans included in this study varied from fully integrated, closed-panel models to plans and delivery systems that include network or independent physician association components. Information derived from the data inventory and data dictionary instruments demonstrated a substantial variation in both the content and capture of data across all sites and across all components of usage. The methods we employed for cost allocation varied by usage component and were based on our ability to leverage the data points available to best reflect actual resource use. CONCLUSIONS: The importance of this article is the method of ascertaining, cataloging, and addressing the within- and between-plan differences in health care resource use. Second, the decisions we made to address the differences between health plans provide other researchers a starting point when creating a cost algorithm for multisite retrospective research.

Health plan administrative databases can efficiently identify serious myopathy and rhabdomyolysis.

OBJECTIVE: We evaluated the positive predictive values (PPVs) of specific criteria based upon International Classification of Diseases, 9th revision (ICD-9-CM) codes documented in health plan administrative databases for identification of cases of serious myopathy and rhabdomyolysis. STUDY DESIGN AND SETTING: We conducted a retrospective study among patients enrolled in 11 geographically dispersed managed care organizations. Cohorts of new users of specific statins and fibrates were identified by selecting patients with an initial dispensing of the drug during the period 1 January 1998 to 30 June 2001. Potential cases of serious myopathy or rhabdomyolysis were identified using specific criteria based upon ICD-9-CM codes suggesting a muscle disorder or acute renal failure. RESULTS: A total of 194 hospitalizations meeting the criteria for chart review selection were identified among 206,732 new users of statins and 15,485 new users of fibrates. Overall, 31 cases of serious, clinically important myopathy or rhabdomyolysis (18%) were confirmed through chart review. Of these, 26 (84%) had a claim including codes for myoglobinuria (ICD-9-CM 791.3) or other disorders of muscle, ligament, and fascia (ICD-9-CM 728.89). A PPV of 74% (26 of 35 patients meeting criteria) was found for a composite definition that included (1) a primary or secondary discharge code for myoglobinuria, (2) a primary code for "other disorders of muscle," or (3) a secondary code for "other disorders of muscle" accompanied by a claim for a CK test within 7 days of hospitalization or a discharge code for acute renal failure. CONCLUSION: For rare adverse events such as serious myopathy or rhabdomyolysis, large population-based databases that include diagnosis and laboratory test claims data can facilitate epidemiologic research.

Births by day of week: a historical perspective.

Our objective was to describe the historical pattern of the decline in weekend births. Data on 906,100 health maintenance organization enrollees' birthdates were analyzed to show patterns of birth by day of week from 1910 to 1999. The decline in Sunday births dates to the 1930s, and the decline in Saturday births dates to the 1950s, far earlier than previously demonstrated in the literature. The expected natural birth process has been significantly modified. By examining a much longer time series than in other literature, it is also possible to see that the trend is not abating and may be increasing.

Opportunities and challenges for measuring cost, quality, and clinical effectiveness in health care.

Empirical studies of health care cost, productivity, and output have focused primarily on intermediate goods and services. Consumers are ultimately interested in final goods such as improved health or health-related quality of life, but health services research continues to address whether health services financing and delivery are structured in ways to maximize production of intermediate goods, regardless of the link between these services and final outcomes. Increasing rates of growth of health care cost and dissatisfaction with the quality of U.S. health care force us to reexamine how productivity and cost are analyzed so that research properly informs policy and practice. The authors examine recent changes in the U.S. health care sector that suggest the need to revise how health services research approaches analyses of cost, production, and output; consider alternative notions of final goods; and review the availability and quality of data necessary to conduct this research.

Issues in pooling administrative data for economic evaluation.

Managed care, in particular the health maintenance organization (HMO), now dominates US healthcare delivery, and economic evaluation is receiving increasing attention as a management tool that can be tailored to its perceived business needs. This encourages use of HMO administrative data as an efficient source of resource utilization and cost measures. Use of administrative data coincides with growing research interest in multisite analyses that increase external validity. The best alternative to a nationally representative data set is to pool administrative data from multiple sites within one database. However, pooling administrative data is problematic because HMO data sources reflect differences in systems of care, costing, and coding. This paper describes issues inherent in the pooling of HMO administrative cost data for use in multisite economic evaluations. We describe the attributes of administrative data that are relevant to costing and discuss their implications for multisite economic evaluations. We then briefly describe our experience with pooling multisite cost data, discuss lessons learned, and offer suggestions for researchers working with such data, followed by concluding comments. Multisite administrative data provide unique opportunities to conduct population-based clinical and economic research.

Does payment drive procedures? Payment for specialty services and procedure rate variations in 3 HMOs.

OBJECTIVE: To study how payment for specialty services affects the rates of performance of invasive procedures by physicians in a number of specialties. STUDY DESIGN: Observational study. PATIENTS AND METHODS: Administrative data from 1996-1997 and 1997-1998 from 3 large health maintenance organizations (HMOs) in the Midwestern and western United States were used to study variations in procedure rates associated with different methods of paying for cardiology, gastroenterology, ophthalmology, orthopedic, and ear, nose and throat services within each HMO. The age-, sex-, and comorbidity adjusted probabilities of undergoing selected, potentially discretionary procedures, were compared within each plan by payment method. RESULTS: After adjustment, rates under fee-for-service payment tended to be higher than those under capitation or salary payment, whereas there was no clear pattern for salary versus capitation payment. Even within a single specialty in a single plan, however, rates did not always follow the same pattern for different procedures. CONCLUSIONS: The payment method for specialty services used by these 3 health plans was variably associated with how likely patients were to undergo a variety of invasive procedures. The effects of contract payment methods for specialty services on health care costs, quality, and outcomes should be further studied, but such studies will challenge the capabilities of health plan data systems.

Secondary gait compensations in individuals without neuromuscular involvement following a unilateral imposed equinus constraint.

Ankle equinus is the most commonly identified impairment of individuals with spastic hemiplegia (SH). However, it is not clear how equinus at the ankle may contribute to gait deviations at other joints. The purpose of this study was to determine what compensatory gait deviations may occur as a result of an imposed, unilateral equinus constraint. Gait data were collected on 12 adult subjects with and without one ankle constrained in equinus using a unique taping method. Knee extension at initial contact, knee extension in mid stance, and hip extension at terminal stance were all found to be significantly reduced on the ipsilateral side as a result of the ankle constraint. On the unconstrained or contralateral side, subjects tended to adopt a foot-flat or toe-first initial contact pattern. This study suggests that stance phase limitations in both hip and knee extension in the gait of persons with hemiplegia are not necessarily caused by limited length of the involved side hamstrings and/or hip flexors, but rather that they can occur as the result of an ankle plantarflexor contracture alone. Deviations in the contralateral foot contact pattern can also occur secondary to unilateral equinus and should not be assumed to represent bilateral involvement.

Incidence of hospitalized rhabdomyolysis in patients treated with lipid-lowering drugs.

CONTEXT: Lipid-lowering agents are widely prescribed in the United States. Reliable estimates of rhabdomyolysis risk with various lipid-lowering agents are not available. OBJECTIVE: To estimate the incidence of rhabdomyolysis in patients treated with different statins and fibrates, alone and in combination, in the ambulatory setting. DESIGN, SETTING, AND PATIENTS: Drug-specific inception cohorts of statin and fibrate users were established using claims data from 11 managed care health plans across the United States. Patients with at least 180 days of prior health plan enrollment were entered into the cohorts between January 1, 1998, and June 30, 2001. Person-time was classified as monotherapy or combined statin-fibrate therapy. MAIN OUTCOME MEASURE: Incidence rates of rhabdomyolysis per 10,000 person-years of treatment, number needed to treat, and relative risk of rhabdomyolysis. RESULTS: In 252,460 patients treated with lipid-lowering agents, 24 cases of hospitalized rhabdomyolysis occurred during treatment. Average incidence per 10,000 person-years for monotherapy with atorvastatin, pravastatin, or simvastatin was 0.44 (95% confidence interval [CI], 0.20-0.84); for cerivastatin, 5.34 (95% CI, 1.46-13.68); and for fibrate, 2.82 (95% CI, 0.58-8.24). By comparison, the incidence during unexposed person-time was 0 (95% CI, 0-0.48; P = .056). The incidence increased to 5.98 (95% CI, 0.72-216.0) for combined therapy of atorvastatin, pravastatin, or simvastatin with a fibrate, and to 1035 (95% CI, 389-2117) for combined cerivastatin-fibrate use. Per year of therapy, the number needed to treat to observe 1 case of rhabdomyolysis was 22,727 for statin monotherapy, 484 for older patients with diabetes mellitus who were treated with both a statin and fibrate, and ranged from 9.7 to 12.7 for patients who were treated with cerivastatin plus fibrate. CONCLUSIONS: Rhabdomyolysis risk was similar and low for monotherapy with atorvastatin, pravastatin, and simvastatin; combined statin-fibrate use increased risk, especially in older patients with diabetes mellitus. Cerivastatin combined with fibrate conferred a risk of approximately 1 in 10 treated patients per year.

Costs and health care resource utilization among chronic obstructive pulmonary disease patients with newly acquired pneumonia.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) are at increased risk for lung infections and other pathologies (eg, pneumonia); however, few studies have evaluated the impact of pneumonia on health care resource utilization and costs in this population. The purpose of this study was to estimate health care resource utilization and costs among COPD patients with newly acquired pneumonia compared to those without pneumonia. METHODS: A retrospective claims analysis using Truven MarketScan(®) Commercial and Medicare databases was conducted. COPD patients with and without newly acquired pneumonia diagnosed between January 1, 2004 and September 30, 2011 were identified. Propensity score matching was used to create a 1:1 matched cohort. Patient demographics, comorbidities (measured by Charlson Comorbidity Index), and medication use were evaluated before and after matching. Health care resource utilization (ie, hospitalizations, emergency room [ER] and outpatient visits), and associated health care costs were assessed during the 12-month follow-up. Logistic regression was conducted to evaluate the risk of hospitalization and ER visits, and gamma regression models and two-part models compared health care costs between groups after matching. RESULTS: In the baseline cohort (N=467,578), patients with newly acquired pneumonia were older (mean age: 70 versus [vs] 63 years) and had higher Charlson Comorbidity Index scores (3.3 vs 2.6) than patients without pneumonia. After propensity score matching, the pneumonia cohort was nine times more likely to have a hospitalization (odds ratio; 95% confidence intervals [CI] =9.2; 8.9, 9.4) and four times more likely to have an ER visit (odds ratio; 95% CI =4.4; 4.3, 4.5) over the 12-month follow-up period compared to the control cohort. The estimated 12-month mean hospitalization costs ($14,353 [95% CI: $14,037-$14,690]), outpatient costs ($6,891 [95% CI: $6,706-$7,070]), and prescription drug costs ($1,104 [95% CI: $1,054-$1,142]) were higher in the pneumonia cohort than in the control cohort. CONCLUSION: This study demonstrated elevated health care resource use and costs in patients with COPD after acquiring pneumonia compared to those without pneumonia.

Development of a practical screening tool to predict low muscle mass using NHANES 1999-2004.

BACKGROUND: Skeletal muscle mass declines after the age of 50. Loss of skeletal muscle mass is associated with increased morbidity and mortality. OBJECTIVE: This study aims to identify predictors of low skeletal muscle mass in older adults toward development of a practical clinical assessment tool for use by clinicians to identify patients requiring dual-energy X-ray absorptiometry (DXA) screening for muscle mass. METHODS: Data were drawn from the National Health and Nutrition Examination Surveys (NHANES) from 1999 to 2004. Appendicular skeletal mass (ASM) was calculated based on DXA scans. Skeletal muscle mass index (SMI) was defined as the ratio of ASM divided by height in square centimeters. Elderly participants were classified as having low muscle mass if the SMI was 1 standard deviation (SD) below the mean SMI of young adults (20-40 years old). Logistic regression was conducted separately in males and females age ≥65 years of age to examine the relationship between patients identified as having low muscle mass and health behavior characteristics, adjusting for comorbid conditions. The model was validated on a separate sample of 200 patients. RESULTS: Among the NHANES study population, 551 (39.7 %) males and 374 (27.5 %) females had a SMI below the 1 SD cutoff point. NHANES study subjects with a low SMI were older (mean age, 76.2 vs. 72.7 for male; 76.0 vs. 73.7 for female; and both p < 0.0001) and had a lower body mass index (mean BMI, 24.1 vs. 29.4 for male; 22.9 vs. 29.7 for female; p < 0.0001). In adjusted logistic regression analyses, age (for males) and BMI (for both males and females) remained statistically significant. A parsimonious logistic regression model adjusting for age and BMI only had a C statistic of 0.89 for both males and females. The discriminatory power of the parsimonious model increased to 0.93 for males and 0.95 for females when the cutoff defining low SMI was set to 2 SD below the SMI of young adults. In the validation sample, the sensitivity was 81.6 % for males and 90.6 % for females. The specificity was 66.2 % for males and females. CONCLUSIONS: BMI was strongly associated with a low SMI and may be an informative predictor in the primary care setting. The predictive model worked well in a validation sample.