PubMed Health⌕ Search

Biomedical subjects

J D Adachi

Publications and source records attributed to J D Adachi.

12 recordsLinked to original sources
PubMed1991

The interchangeability of radioisotope and X-ray based measurements of bone mineral density.

Lumbar spine and femoral neck bone mineral density (BMD) were measured with a Novo radioisotope based dual photon densitometer and with a Lunar X-ray densitometer in 94 subjects attending a Metabolic Bone Disease Clinic. There was a strong correlation between results obtained from each machine for the same skeletal site. The correlation coefficients for the spine and femoral neck were 0.97 and 0.88, respectively. The differences between results from each machine were normally distributed with a mean bias of 37.5% for the spine and 27.8% for the femur, which arise principally from differences in machine calibration. In each case the BMD was greater when measured by X-ray absorptiometry. The range for the bias was approximately 25-50% for the spine and 10-45% for the femoral neck. The results from these two machines are not interchangeable. When subjects who are participating in long term studies using a radioisotope densitometer are transferred to an X-ray densitometer, an individual conversion factor must be measured at each site for each subject.

Absorptiometry, Photon↗
PubMed1990

The n-of-1 randomized controlled trial: clinical usefulness. Our three-year experience.

OBJECTIVE: To review the feasibility and effectiveness of n-of-1 randomized controlled trials (n-of-1 trials) in clinical practice. DESIGN: Individual trials were double-blind, randomized, multiple crossover trials. The impact of n-of-1 trials was determined by eliciting physicians' plans of management and confidence in those plans before and after each trial. SETTING: Referral service doing n-of-1 trials at the requests of community and academic physicians. OBJECT of ANALYSIS: All trials were planned, started, and completed by the n-of-1 service. MEASURES OF OUTCOME: The proportion of planned n-of-1 trials that were completed and the proportion that provided a definite clinical or statistical answer. A definite clinical answer was achieved if an n-of-1 trial resulted in a high level of physician's confidence in the management plan. Specific criteria were developed for classifying an n-of-1 trial as providing a definite statistical answer. MAIN RESULTS: Seventy-three n-of-1 trials were planned in various clinical situations. Of 70 n-of-1 trials begun, 57 were completed. The reasons for not completing n-of-1 trials were patients' or physicians' noncompliance or patients' concurrent illness. Of 57 n-of-1 trials completed, 50 provided a definite clinical or statistical answer. In 15 trials (39% of trials in which appropriate data were available), the results prompted physicians to change their "prior to the trial" plan of management (in 11 trials, the physicians stopped the drug therapy that they had planned to continue indefinitely). CONCLUSION: We interpret the results as supporting the feasibility and usefulness of n-of-1 trials in clinical practice.

Adult↗
PubMed1990

N of 1 randomized trials for investigating new drugs.

Presently, in the process of new drug development, large sample parallel group randomized trials are often begun without the detailed knowledge of optimal dose, most responsive patient group, and optimal outcomes which would be desirable. We propose that randomized trials in individual subjects (N of 1 RCTs) could be used to elucidate these issues at an early stage of drug development. In appropriate conditions N of 1 RCTs can be used to define the rapidity with which a drug begins and ceases its clinical action, the likely range of the optimal drug dose, and the optimal outcomes on which subsequent trials should focus. N of 1 RCTs can also generate initial estimates of the proportion of patients who respond to a new agent and for determining sample size, inclusion criteria, and dosage regimen(s) for subsequent parallel group trials. We provide an example of 14 N of 1 RCTs of amitriptyline in fibrositis that illustrate the ways in which N of 1 RCTs can elucidate these issues. The multiple uses of N of 1 RCTs suggest that the method has immense potential for use in the early phases of drug development programs.

Amitriptyline↗
PubMed1990

Bone densitometry.

Explore the source record for details and available documents.

Absorptiometry, Photon↗
PubMed1988

An N of 1 service: applying the scientific method in clinical practice.

The N of 1 service at our institution acts as a full referral service for clinicians who want a definitive answer to a difficult management question, and an instructional environment for clinicians who have more time and want to learn to run their own N of 1 RCT. The trial design is a double blind, randomized pair, multiple crossover. A number of methodologic issues are discussed, such as appropriateness of the patients problem to N of 1 trials, feasibility, types of measurement, such as clinical objective measurement and quality of life measurement, as well as timing of these measurements. The analysis issues include developing a reporting method which is statistically powerful and understandable to clinicians with little research background. Some of these issues have been well investigated and some have not.

Clinical Trials as Topic↗
PubMed1987

HLA-DQ beta-chain polymorphism in HLA-DR4 haplotypes associated with rheumatoid arthritis.

With a cDNA probe for the DQ beta gene, two variants of the DR4-linked DQw3 (3.1 and 3.2) allele were analysed in patients with rheumatoid arthritis (RA), healthy individuals, and homozygous cell lines. The DQw3.1 allele, identified by 3.4 kb (HindIII), 2.3 kb (SstI), and 3.7 kb and 6.9 kb (BamHI) restriction fragment lengths, was expressed in 100% (of 18) DR4-positive patients, compared with only 19% (of 16) of DR4-positive controls including one of five homozygous cell lines. This DQ beta variant showed a highly significant association (relative risk = 78; p less than 10(-6) with RA and may therefore play an important part in susceptibility to RA.

Arthritis, Rheumatoid↗
PubMed1987

Gold induced thrombocytopenia: 12 cases and a review of the literature.

Gold induced thrombocytopenia is immune mediated, with the production of platelet associated IgG leading to peripheral platelet destruction. An association with HLA-DR3 has been demonstrated. Corticosteroid therapy is effective in treatment, although other modes of therapy may be as efficacious.

Arthritis, Rheumatoid↗