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David T Felson

Publications and source records attributed to David T Felson.

At least 19 recordsLinked to original sources
PubMed2026

Sensor-based measures of knee brace adherence have low agreement with self-report methods: A multi-measure study among knee osteoarthritis patients.

OBJECTIVE: To explore agreement between self-report and objectively measured adherence to brace wearing by patients with knee osteoarthritis. METHOD: A single-arm observational analysis nested within the PROP OA randomised controlled trial (ISRCTN28555470). Of 237 adults with symptomatic knee osteoarthritis randomised to brace treatment, 60 were included in this sub-study investigating three different methods of assessing knee brace wear time over 26 weeks: 1. Self-report questionnaires (SRQ) at 12 weeks and 26 weeks; 2. Short message service (SMS) questions (days worn in past week, typical hours per day when worn) administered from week 1 to week 24; 3. A skin temperature sensor embedded in the brace, sampling every 10 min for 26 weeks. The presence and reason for the sensor were concealed from participants. The estimated proportion of participants meeting "minimum brace use", defined a priori as ≥1 h on ≥2 days in past week, was described for each measurement method, overall and by brace type (unloader, neutral). For temperature sensor measurements, time spent above 24°C and time spent above 25°C were used. Agreement between the measures was summarised by percentage agreement and kappa (ĸ). RESULTS: The estimated proportions of participants meeting "minimum brace use" at 12 weeks were 83% (SRQ), 83% (SMS), 60% and 58% (temperature sensor, 24°C and 25°C thresholds, respectively). At 26 weeks, the corresponding estimates reduced to 72%, 71% (SMS at 24 weeks), 43% and 37%. Sensor data suggested the sharpest decline in brace use occurred within the first 12 weeks. Agreement between self-report measures was higher than between self-report measures and sensor (SRQ vs SMS at 12 weeks: 92% agreement, ĸ=0.67 (95%CI: 0.34, 1.00); SRQ vs Sensor at 12 weeks: 74%, 0.35 (0.10, 0.60); SMS vs Sens at 12 weeks: 76%, 0.36 (0.05, 0.66). Agreement between all measurement methods reduced at 26 weeks. CONCLUSIONS: This novel use of a temperature sensor to monitor brace adherence in knee osteoarthritis indicates that self-report adherence substantially overestimates knee brace wearing time, with implications for clinical trials and practice.

Humans↗
PubMed2003

Bone marrow edema and its relation to progression of knee osteoarthritis.

BACKGROUND: While factors affecting the course of knee osteoarthritis are mostly unknown, lesions on bone scan and mechanical malalignment increase risk for radiographic deterioration. Bone marrow edema lesions on magnetic resonance imaging correspond to bone scan lesions. OBJECTIVE: To determine whether edema lesions in the subarticular bone in patients with knee osteoarthritis identify knees at high risk for radiographic progression and whether these lesions are associated with limb malalignment. DESIGN: Natural history study. SETTING: A Veterans Administration hospital in Boston, Massachusetts. PATIENTS: Persons 45 years of age and older with symptomatic knee osteoarthritis. MEASUREMENTS: Baseline assessments included magnetic resonance imaging of the knee and fluoroscopically positioned radiography. During follow-up at 15 and 30 months, patients underwent repeated radiography; at 15 months, long-limb films were obtained to assess mechanical alignment. Progression was defined as an increase over follow-up in medial or lateral joint space narrowing, based on a semi-quantitative grading. Generalized estimating equations were used to evaluate the relation of medial bone marrow edema lesions to medial progression and lateral lesions to lateral progression, before and after adjustment for limb alignment. RESULTS: Of 256 patients, 223 (87.1%) participated in at least one follow-up examination. Medial bone marrow lesions were seen mostly in patients with varus limbs, and lateral lesions were seen mostly in those with valgus limbs. Twenty-seven of 75 knees with medial lesions (36.0%) showed medial progression versus 12 of 148 knees without lesions (8.1%) (odds ratio for progression, 6.5 [95% CI, 3.0 to 14.0]). Approximately 69% of knees that progressed medially had medial lesions, and lateral lesions conferred a marked risk for lateral progression. These increased risks were attenuated by 37% to 53% after adjustment for limb alignment. CONCLUSION: Bone marrow edema is a potent risk factor for structural deterioration in knee osteoarthritis, and its relation to progression is explained in part by its association with limb alignment.

Aged↗
PubMed2003

[High prevalence of knee, but not hip or hand osteoarthritis in Beijing elders: comparison with data of Caucasian in United States].

OBJECTIVE: To investigate the prevalence of knee, hip and hand osteoarthritis (OA) in the elderly of Beijing and to compare the prevalence of OA between the Beijing elders and the US Caucasians. METHODS: Using the same standardized instruments and protocol as those in the Framingham Osteoarthritis Study, home interview, clinical examination and radiography were conducted among 1012 males and 1507 females, all aged 60 and over, on 4 central districts of Beijing with informed consent. The data of survey were compared with those of the corresponding US study. RESULTS: The prevalence of radiographic and symptomatic knee osteoarthritis was 42.8% and 15.4% respectively among the women aged 60 and over in Beijing, higher than those in Caucasian women of the same age. The prevalence of radiographic and symptomatic knee osteoarthritis were 27.6% and 7.1% respectively among the men aged 60 and over in Beijing, similar to those in the Caucasian men of the same age. The prevalence of radiographic hand osteoarthritis among the Beijing men and women aged 60 and over were 44.5% and 47.0% respectively, lower than those among the contemporary Caucasian in US. The prevalence of hip osteoarthritis among the men and women aged 60 and over were only 0.4% and 0.6%, significantly lower than those among the contemporary Caucasian in US. CONCLUSION: Compared to the Caucasian contemporaries, fewer Beijing elderly suffer from hand and hip osteoarthritis. However, knee osteoarthritis is much more prevalent, affecting millions of elderly Chinese.

Aged↗
PubMed2003

Lower prevalence of hand osteoarthritis among Chinese subjects in Beijing compared with white subjects in the United States: the Beijing Osteoarthritis Study.

OBJECTIVE: Fewer Chinese subjects in Beijing have hip osteoarthritis (OA) compared with whites in the United States, but as many or more Chinese subjects have knee OA. If these differences are due to a systemic predilection for disease, then the prevalence of hand OA, the best indicator of generalized disease, should be different in China. The goals of this study were to estimate the prevalence of hand OA among elderly Chinese in Beijing, and to compare it with that among elderly whites in the United States. METHODS: We recruited a random sample of Beijing residents ages > or =60 years. Subjects answered questions on joint symptoms and provided posteroanterior radiographs of the hand. The protocol was identical to that used in the Framingham, Massachusetts OA Study. The hand radiographs from the Beijing OA Study were read intermingled with films from the Framingham OA Study. We defined a hand joint as having radiographic OA if it had a Kellgren and Lawrence grade >/=2. Symptomatic OA was present when both radiographic OA and self-reported pain were present in the same joint. We classified a subject as having radiographic or symptomatic hand OA if at least 1 hand joint had radiographic or symptomatic OA. We estimated the prevalence of hand OA in elderly subjects in Beijing and compared it with the prevalence of hand OA in elderly subjects from Framingham, using an age-standardized prevalence ratio. RESULTS: We obtained both symptom information and hand radiographs from 2,525 subjects. Despite the older age of the group, only 44.5% of men and 47.0% of women had radiographic hand OA. Symptomatic hand OA occurred in 3.0% of men and 5.8% of women. Compared with white men in Framingham, the Beijing Chinese men had a much lower prevalence of radiographic hand OA (age-adjusted prevalence ratio 0.64, 95% confidence interval [95% CI] 0.58-0.70) and symptomatic hand OA (age-adjusted prevalence ratio 0.25, 95% CI 0.16-0.34). The proportion of multiple hand joints affected by OA in Chinese men was also significantly lower than in white men. A similar magnitude of difference was also observed in the women. However, prevalence of symptomatic OA at the metacarpophalangeal (MCP) joints in Chinese men and prevalence of radiographic OA at the MCP joints in Chinese women were similar to those in their white counterparts in Framingham. CONCLUSION: Elderly Chinese subjects in Beijing had a much lower prevalence of hand OA than did elderly whites in Framingham, Massachusetts. Coupled with the exceedingly low prevalence of hip OA in China, these results may suggest that the overall predilection for OA is less among subjects in China than among whites in the United States.

Aged↗
PubMed2003

Hierarchy of evidence: from case reports to randomized controlled trials.

In the hierarchy of research designs, the results of randomized controlled trials are considered the highest level of evidence. Randomization is the only method for controlling for known and unknown prognostic factors between two comparison groups. Lack of randomization predisposes a study to potentially important imbalances in baseline characteristics between two study groups. There is a hierarchy of evidence, with randomized controlled trials at the top, controlled observational studies in the middle, and uncontrolled studies and opinion at the bottom. This hierarchy has not been supported in two recent publications in the New England Journal of Medicine which identified nonsignificant differences in results between randomized, controlled trials, and observational studies. The current authors provide an approach to organizing published research on the basis of study design, a hierarchy of evidence, a set of principles and tools that help clinicians distinguish ignorance of evidence from real scientific uncertainty, distinguish evidence from unsubstantiated opinions, and ultimately provide better patient care.

Evidence-Based Medicine↗
PubMed2003

The clinical importance of meniscal tears demonstrated by magnetic resonance imaging in osteoarthritis of the knee.

BACKGROUND: Meniscal tears are frequently found during magnetic resonance imaging of osteoarthritic knees. However, the prevalence and clinical relevance of these tears have not been determined. This study was designed to investigate the relationship between meniscal tears and osteoarthritis and between such tears and pain in patients with osteoarthritis. METHODS: Magnetic resonance imaging and plain radiography of the knee were performed in a group of 154 patients with clinical symptoms of knee osteoarthritis and a group of forty-nine age-matched asymptomatic controls. Pain scores (according to a 100-mm visual analog scale) and functional scores (according to the Western Ontario and McMaster University Osteoarthritis Index [WOMAC]) were determined for ninety-one of the patients with symptomatic osteoarthritis. Meniscal tears were defined as tears extending to an articular surface as seen on magnetic resonance imaging. RESULTS: A medial or lateral meniscal tear was a very common finding in the asymptomatic subjects (prevalence, 76%) but was more common in the patients with symptomatic osteoarthritis (91%) (p < 0.005). In the group with symptomatic osteoarthritis, a higher Kellgren-Lawrence radiographic grade was correlated with a higher frequency of meniscal tears (r = 0.26, p < 0.001), and men had a higher prevalence of meniscal tears than did women (p < 0.01). However, there was no significant difference with regard to the pain or WOMAC score between the patients with and those without a medial or lateral meniscal tear in the osteoarthritic group (p = 0.8 to 0.9 for all comparisons). The power of the study was 80% to detect a difference in the WOMAC scores of 15 points and a difference in the scores on the visual analog scale of 16 mm. CONCLUSIONS: Meniscal tears are highly prevalent in both asymptomatic and clinically osteoarthritic knees of older individuals. However, osteoarthritic knees with a meniscal tear are not more painful than those without a tear, and the meniscal tears do not affect functional status. These data do not support the routine use of magnetic resonance imaging for the evaluation and management of meniscal tears in patients with osteoarthritis of the knee. LEVEL OF EVIDENCE: Diagnostic study, Level I-1 (testing of previously developed diagnostic criteria in series of consecutive patients [with universally applied reference "gold" standard]). See p. 2 for complete description of levels of evidence.

Age Factors↗
PubMed2003

Deriving an operational definition of low disease activity state in rheumatoid arthritis.

This article summarizes the process proposed to come to a definition of low disease activity in rheumatoid arthritis (RA). The purpose of this definition is to aid the interpretation of trial and longitudinal study results. A conceptual proposal is "a disease activity state that is deemed a useful treatment target by both physicians and patients." An operant definition can be derived by judgmental (opinion-based) or statistical (data-based) approaches, but the first seems more appropriate. Once a few candidate definitions have been selected, their usefulness and prognostic validity can be tested in longitudinal datasets.

Arthritis, Rheumatoid↗
PubMed2002

Bone mass and the risk of prostate cancer: the Framingham Study.

PURPOSE: To examine the relation of bone mass-a potential biologic marker for cumulative exposure to androgens, insulin-like growth factors, and calcium intake-to subsequent development of prostate cancer. METHODS: We used radiogrammetry to measure the second metacarpal cortical area of 1012 white men with no history of prostate cancer who had undergone posteroanterior hand radiography between 1967 and 1970. Participants were followed until the end of 1999. All incident cases of prostate cancer were confirmed histologically. We examined bone mass in relation to the risk of prostate cancer using a Cox proportional hazards model. RESULTS: During follow-up, 100 men developed prostate cancer. Incidence rates per 1000 person-years were 3.8 among men in the lowest quartile of bone mass, 4.8 in the second quartile, 7.4 in the third quartile, and 6.5 in the highest quartile. Compared with men in the lowest quartile of bone mass, the multivariate-adjusted rate ratio was 1.3 (95% confidence interval [CI]: 0.7 to 2.5) for those in the second quartile, 1.9 (95% CI: 1.0 to 3.4) in the third quartile, and 1.6 (95% CI: 0.9 to 3.0) in the highest quartile (P for trend = 0.06). CONCLUSION: Men with high bone mass may be at an increased risk of prostate cancer. Although the biological mechanisms underlying this relation are not understood, cumulative exposure to high levels of androgen, insulin-like growth factor 1, or calcium intake may be involved.

Bone and Bones↗
PubMed2002

Truth survival.

Explore the source record for details and available documents.

Bias↗
PubMed2002

Prevalence of symptomatic hand osteoarthritis and its impact on functional status among the elderly: The Framingham Study.

Osteoarthritis is one of the most common joint disorders in the elderly, yet few studies have targeted symptomatic osteoarthritis, especially symptomatic hand osteoarthritis. The authors conducted a survey in 1992-1993 among an elderly population to estimate the prevalence of symptomatic hand osteoarthritis and to assess its impact on grip strength and functional activities. Framingham Study subjects received hand radiographs and answered queries on joint symptoms. Functional activities were assessed using an interviewer-administered questionnaire. Grip strength and observed functional performance were evaluated using standard procedures. A hand joint was defined as having symptomatic osteoarthritis if both symptoms and radiographic evidence of osteoarthritis were present. Of 1,041 subjects aged 71-100 years (36% men), the prevalence of symptomatic hand osteoarthritis was higher in women (26.2%) than in men (13.4%). Compared with those without symptomatic hand osteoarthritis, subjects with the disease had 10% reduced maximal grip strength, reported more difficulty writing, handling, or fingering small objects (odds ratio = 3.4), and showed more self-reported and observed difficulty carrying a 10-pound (4.5-kg) bundle (odds ratio = 1.7 and 1.6, respectively). In conclusion, in the context of a remarkable paucity of data on the epidemiology of symptomatic hand osteoarthritis, this study suggests that symptomatic hand osteoarthritis is a common disease among elders and frequently impairs hand function.

Activities of Daily Living↗
PubMed2002

Statistical presentation and analysis of ordered categorical outcome data in rheumatology journals.

OBJECTIVE: To assess the appropriateness of presentation of summary measures and analysis of ordered categorical (ordinal) data in three rheumatology journals in 1999, and to consider differences between basic and clinical science articles. METHODS: Six hundred forty-four full-length articles from the 1999 editions of 3 rheumatology journals were evaluated for inclusion of an ordinal outcome. Articles were classified as basic or clinical science, and the appropriateness of presentation and analysis of the ordinal outcome were assessed. Chi-square tests were used to evaluate difference in percentages. RESULTS: Ordinal outcomes were identified in 175 (27.2%) of 644 articles. Only 69 (39.4%) had appropriate data presentation, and 111 (63.4%) had appropriate data analysis. Appropriate presentation was seen less commonly in the basic science rather than the clinical science articles, but differences in the occurrence of appropriate analysis were not seen. CONCLUSION: Ordinal data are common in rheumatology articles, but presentation usually does not conform to recommended guidelines.

Data Collection↗
PubMed2002

High prevalence of lateral knee osteoarthritis in Beijing Chinese compared with Framingham Caucasian subjects.

OBJECTIVE: We recently reported that, despite their thinness, elderly subjects in Beijing, China had an equal prevalence (in men) or higher prevalence (in women) of both radiographic and symptomatic knee osteoarthritis (OA) compared with that in the Framingham, Massachusetts cohort of elderly subjects. Our objective was to evaluate whether Chinese subjects might have more medial disease than do Caucasians, given a report of varus alignment in the knee joints of Chinese elderly. METHODS: We compared the prevalence of medial and lateral radiographic knee OA and measured anatomic alignment in the knees of elderly subjects from the Beijing and Framingham cohorts. Both studies recruited a random sample of the population. The Beijing OA Study used the Framingham OA Study protocol for radiographs. Anteroposterior weight-bearing films were read for Kellgren and Lawrence (K/L) grade and joint space narrowing (JSN; 0-3 scale) in each compartment. Medial disease was defined when radiographs showed a K/L grade >or=2 and medial JSN >or=1, and lateral disease was assessed in a comparable manner. Using knee-specific analyses, we compared the prevalence of medial and lateral knee OA after adjusting for age, body mass index, and the correlation between the 2 knees. Restricting the analyses to knees with JSN >or=2 and comparing the proportion of OA knees with medial disease and lateral disease yielded similar results. We assessed alignment in knees from 100 persons without OA, measuring the angle subtended by the femoral and tibial anatomic axes. RESULTS: We studied 1,781 Chinese subjects ages 60-88 years, and 1,084 Framingham subjects ages 63-93 years. Whereas medial OA was less prevalent among the Beijing men, lateral OA was more than twice as prevalent among the Beijing men and women, compared with that in the Framingham elderly. For example, of all knees with radiographic OA, 28.5% of Beijing women's knees had lateral OA versus 11% of Framingham women's knees (P < 0.001), and among men, 32.3% of Beijing men's knees versus 8.8% of Framingham men's knees (P < 0.001) had lateral OA. Alignment was more valgus in the Beijing men than in the Framingham men (mean 4.5 degrees versus 2.7 degrees valgus, respectively; P < 0.001), but no differences in alignment were evident in the women. CONCLUSION: In this first attempt to compare the characteristics of OA in different racial groups, we conclude that, opposite to expectations, Chinese subjects have much more lateral OA than do Caucasian subjects in the Framingham cohort, a predilection possibly explained in the men by differences in anatomic alignment.

Aged↗
PubMed2002

Very low prevalence of hip osteoarthritis among Chinese elderly in Beijing, China, compared with whites in the United States: the Beijing osteoarthritis study.

OBJECTIVE: To compare the prevalence of osteoarthritis (OA) of the hip among elderly persons in China and the US. METHODS: We recruited a population-based sample of 1,506 persons (82% of those enumerated) ages > or = 60 years living in Beijing, China. Subjects answered questions about joint symptoms and underwent radiography of the pelvis. Radiographs of the Beijing subjects were intermingled with hip radiographs of white women ages > or = 65 years from the Study of Osteoporotic Fractures (SOF) and white men and women ages 60-74 years from the First National Health and Nutrition Examination Survey (NHANES-I) and were then interpreted. Radiographic hip OA was defined as the presence of 1 of the following 3 findings in either hip: minimum joint space of < or = 1.5 mm, definite osteophytes and joint space narrowing, or > or = 3 radiographic features of OA. Symptomatic hip OA was defined as both radiographic OA and hip pain. RESULTS: The crude prevalence of radiographic hip OA in Chinese ages 60-89 years was 0.9% in women and 1.1% in men; it did not increase with age. Chinese women had a lower age-standardized prevalence of radiographic hip OA compared with white women in the SOF (age-standardized prevalence ratio 0.07) and the NHANES-I (prevalence ratio 0.22). Chinese men had a lower prevalence of radiographic hip OA compared with white men of the same age in the NHANES-I (prevalence ratio 0.19). There were no cases of symptomatic hip OA in the Chinese men and only 1 case in the Chinese women; 35 cases were expected in both sexes. CONCLUSION: This is the first population-based study of hip OA in China to use standardized radiographic methods and definitions. We found that hip OA was 80-90% less frequent than in white persons in the US. Identification of the genetic and environmental factors that underlie these differences may help elucidate the etiology and prevention of hip OA.

Aged↗
PubMed2002

Secular changes in the quality of published randomized clinical trials in rheumatology.

OBJECTIVE: To assess the quality of published randomized clinical trials (RCTs) in rheumatology and to determine whether there has been improvement in quality between 2 time periods, 1987-1988 and 1997-1998. METHODS: Using MEDLINE and a hand search of selected rheumatology journals, we identified RCTs of adult rheumatic diseases published in English in 1987-1988 or 1997-1998. We examined trial quality with an expanded version of the Jadad scale, which assesses the adequacy of reported random sequence generation, allocation concealment, blinding, and analysis. All trials were read by 1 reviewer, with prior standardization using a random sample read by 2 reviewers. We also evaluated "high"- versus "low"-impact journals based on citation index. RESULTS: Two hundred forty RCTs (1987-1988 119 RCTs, 1997-1998 121 RCTs) were assessed. Results showed improvement in the quality of the trials, but the rates of reported random sequence generation, allocation concealment, power, and intent-to-treat analyses were persistently low. Low rates of reports of random sequence generation, allocation concealment, and intent-to-treat analyses were present even in the high-impact journals. CONCLUSION: There has been improvement in the quality of reporting of RCTs in rheumatology between 1987-1988 and 1997-1998. However, methodologic problems such as lack of allocation concealment, inadequate random sequence generation, lack of reporting of power, and lack of intent-to-treat analyses remain common. Many of these problems are established sources of bias in RCTs and are easily rectifiable.

Humans↗