Performance of risk assessment instruments for predicting osteoporotic fracture risk: a systematic review

Abstract

Summary We systematically reviewed the literature on the performance of osteoporosis absolute fracture risk assessment instruments. Relatively few studies have evaluated the calibration of instruments in populations separate from their development cohorts, and findings are mixed. Many studies had methodological limitations making susceptibility to bias a concern. Introduction The aim of this study was to systematically review the literature on the performance of osteoporosis clinical fracture risk assessment instruments for predicting absolute fracture risk, or calibration, in populations other than their derivation cohorts. Methods We performed a systematic review, and MEDLINE, Embase, Cochrane Library, and multiple other literature sources were searched. Inclusion and exclusion criteria were applied and data extracted, including information about study participants, study design, potential sources of bias, and predicted and observed fracture probabilities. Results A total of 19,949 unique records were identified for review. Fourteen studies met inclusion criteria. There was substantial heterogeneity among included studies. Six studies assessed the WHO's Fracture Risk Assessment (FRAX) instrument in five separate cohorts, and a variety of risk assessment instruments were evaluated in the remainder of the studies. Approximately half found good instrument calibration, with observed fracture probabilities being close to predicted probabilities for different risk categories. Studies that assessed the calibration of FRAX found mixed performance in different populations. A similar proportion of studies that evaluated simple risk assessment instruments (≤5 variables) found good calibration when compared with studies that assessed complex instruments (>5 variables). Many studies had methodological features making them susceptible to bias. Conclusions Few studies have evaluated the performance or calibration of osteoporosis fracture risk assessment instruments in populations separate from their development cohorts. Findings are mixed, and many studies had methodological limitations making susceptibility to bias a possibility, raising concerns about use of these tools outside of the original derivation cohorts. Further studies are needed to assess the calibration of instruments in different populations prior to widespread use.

Can FRAX Tool be Used for Determination of Risk Score for Osteoporosis Fractures in a Financially Constrained Society Like Bangladesh?

“…Among them, age, past history of fracture and low BMD are known as the strongest risk factors for the likelihood of fracture. 12,13 Therefore, it is incumbent upon the clinical practitioner to identify patients in whom treatment will result in the greatest benefit while avoiding treatment of low-risk individuals where the expectation of benefit is small. The FRAX, developed by the WHO Collaborating Centre for Metabolic Bone Diseases, allows for the estimation of individual fracture risk based upon that individual's risk factor profile.…”

“…11 The adoption of 10-year fracture risk reporting in clinical practice has been shown to beneficial impact on prescribing practices by physicians through better alignment of treatment initiation with the patient's actual risk when compared with a BMD T-score alone. 12 Not with standing the substantial impact of FRAX on clinical practice and its increasing use in clinical practice guidelines, 8,[13][14][15] questions remain on how to improve FRAX and better inform those who use FRAX in clinical practice. FRAX model's usefulness had been verified by several studies so far.…”

“…However, the intervention threshold for osteoporosis is not yet established. 12,13 Now, under the auspices of the National Osteoporosis Guideline Group, 10 professional bodies and patients' organizations have developed an evidence-based management guideline for both men and postmenopausal women aged over 50. 16 NOFG recommends treating patients with FRAX 10-year risk scores of ≥ 3% for hip fracture or ≥ 20% for major osteoporotic fracture, to reduce their fracture risk 9 .…”

Riesgo de fractura en la cohorte FRODOS: estudio comparativo de la aplicación del modelo FRAX® español, francés, inglés y sueco

“…Without denying the merit of their having been the first works which recorded in an organised way the epidemiology of femoral fractures in our country, the representativeness of the Spanish cohorts included in the original development of FRAX ® has been questioned, principally for not using in all cases population-based studies, but also due to the low number of individuals and events included, and the great variability in the incidence of fractures between the different autonomous communities of Spain 8,19 . Ideally, in order for a model for the prediction of clinical risk such as FRAX ® to be used with confidence in daily clinical practice it ought to comply with at least two conditions: having demonstrated its validity in other population groups similar to the original ones; and helping to resolve problems for users less experienced in the field of osteoporosis, be they general practitioners or health care planners [20][21][22] . It is evident that if the first point is not complied with there should not be a move towards the generalisation of its use since we would be doing this on an inappropriate basis 2,8,17,[20][21][22] .…”

“…Ideally, in order for a model for the prediction of clinical risk such as FRAX ® to be used with confidence in daily clinical practice it ought to comply with at least two conditions: having demonstrated its validity in other population groups similar to the original ones; and helping to resolve problems for users less experienced in the field of osteoporosis, be they general practitioners or health care planners [20][21][22] . It is evident that if the first point is not complied with there should not be a move towards the generalisation of its use since we would be doing this on an inappropriate basis 2,8,17,[20][21][22] . The Spanish FRAX ® model has been evaluated in three cohort studies 5-7 which clearly differ, but which, in having a sufficient number of participants and events, agree in their conclusions: the Spanish FRAX ® model clearly predicts a lower number of POFs than are observed, while the prediction of FFs is somewhat closer to what actually happens; however, the predictive power measured by the area under the curve of the ROC curves is no higher than 70%.…”