Death certification and epidemiological research. Medical Services Study Group of the Royal College of Physicians of London.

The cause of death shown on 191 death certificates was compared with the cause indicated by the hospital case notes, the consultants'' opinions, and the necropsy findings. All 191 deaths occurred among medical hospital patients aged under 50. In 39 cases there was a major discrepancy between the two sources over the cause of death and in another 54 ther was a minor but epidemiologically important difference. Death certificates are not primarily intended for epidemiological research, but researchers often rely on them. This and other studies have shown, however, that death certificates are often inaccurate records of the cause of death--even coroner''s certificates issued after a coroner''s necropsy. The accuracy of death certificates might be improved if coroners consulted clinicians more closely and if senior hospital staff completed hospital death certificates.     

Prognostic index for recurrence of seizures after remission of epilepsy. Medical Research Council Antiepileptic Drug Withdrawal Study Group.

OBJECTIVES--To develop and test a prognostic index for the recurrence of seizures after a minimum remission of seizures of two years in people with a history of epilepsy. DESIGN--Information from a large prospective randomised study of withdrawal of antiepileptic drugs was used to identify clinical and treatment factors of prognostic importance in determining the recurrence of seizures. A split sample approach was used to test the internal validity of predictions made on the basis of identified prognostic factors. SETTING--Centres in six European countries. MAIN OUTCOME MEASURES--Comparison of predicted and observed rates of recurrence of seizure. SUBJECTS--1013 patients randomised to the Medical Research Council study for antiepileptic drug withdrawal. RESULTS--The Cox proportional hazards model identified several factors that increased the risk of seizures recurring. These included being 16 years or older; taking more than one antiepileptic drug; experiencing seizures after starting antiepileptic drug treatment; a history of primary or secondarily generalised tonic-clonic seizures; a history of myoclonic seizures; and having an abnormal electroencephalogram. The risks of seizures recurring decreased with increasing time without seizures. The model allowed estimation of the risk of seizures recurring in the next one and two years under the policies of continued antiepileptic drug treatment and slow withdrawal of drugs. Split sample validation suggested that the model was well calibrated. CONCLUSION--The model is currently the best available aid for counselling the many patients in the community with epilepsy currently in remission who seek advice about the risks of seizures recurring if they stop antiepileptic drug treatment. The model requires validation in a broad population of patients, and such studies are in progress.     

Auditing audits: use and development of the Oxfordshire Medical Audit Advisory Group rating system.

OBJECTIVES--To assess the value of the Oxfordshire Medical Audit Advisory Group rating system in monitoring and stimulating audit activity, and to implement a development of the system. DESIGN--Use of the rating system for assessment of practice audits on three annual visits in Oxfordshire; development and use of an "audit grid" as a refinement of the system; questionnaire to all medical audit advisory groups in England and Wales. SETTING--All 85 general practices in Oxfordshire; all 95 medical audit advisory groups in England and Wales. MAIN OUTCOME MEASURES--Level of practices'' audit activity as measured by rating scale and grid. Use of scale nationally together with perceptions of strengths and weaknesses as perceived by chairs of medical audit advisory groups. RESULTS--After one year Oxfordshire practices more than attained the target standards set in 1991, with 72% doing audit involving setting target standards or implementing change; by 1993 this had risen to 78%. Most audits were confined to chronic disease management, preventive care, and appointments. 38 of 92 medical audit advisory groups used the Oxfordshire group''s rating scale. Its main weaknesses were insensitivity in assessing the quality of audits and failure to measure team involvement. CONCLUSIONS--The rating system is effective educationally in helping practices improve and summatively for providing feedback to family health service authorities. The grid showed up weakness in the breadth of audit topics studied. IMPLICATIONS AND ACTION--Oxfordshire practices achieved targets set for 1991-2 but need to broaden the scope of their audits and the topics studied. The advisory group''s targets for 1994-5 are for 50% of practices to achieve an audit in each of the areas of clinical care, access, communication, and professional values and for 80% of audits to include setting targets or implementing change.     

Applications and Enrolments at the Western Medical Schools: A Study of Medical Matriculants for 1964

All applicants and those who subsequently enrolled for the 1964-65 session in the Western medical schools were studied with the hope that it would encourage a national registration of applicants. Seven hundred and sixty-four applicants completed 865 applications for 288 places in four schools. Although the principal factor in selecting medical students in all Western schools is pre-medical performance, 49 “good-quality” (academically of good standing and under 30 years of age) resident applicants were not accepted in their own provincial school, and 49 places were filled with “poor-quality” students.The loss of good applicants to the Western medical schools and the 20% overlap of each school''s applicant pool with that of other schools suggests that objective standards of quality must be developed, and that a regular annual national assessment of applicants should be conducted by the Association of Canadian Medical Colleges.     

Spectral compensation for flow cytometry: visualization artifacts, limitations, and caveats.

BACKGROUND: In multicolor flow cytometric analysis, compensation for spectral overlap is nearly always necessary. For the most part, such compensation has been relatively simple, producing the desired rectilinear distributions. However, in the realm of multicolor analysis, visualization of compensated often results in unexpected distributions, principally the appearance of a large number of events on the axis, and even more disconcerting, an inability to bring the extent of compensated data down to "autofluorescence" levels. MATERIALS AND METHODS: A mathematical model of detector measurements with variable photon intensities, spillover parameters, measurement errors, and data storage characteristics was used to illustrate sources of apparent error in compensated data. Immunofluorescently stained cells were collected under conditions of limiting light collection and high spillover between detectors to confirm aspects of the model. RESULTS: Photon-counting statistics contribute a nonlinear error to compensated parameters. Measurement errors and log-scale binning error contribute linear errors to compensated parameters. These errors are most apparent with the use of red or far-red fluorochromes (where the emitted light is at low intensity) and with large spillover between detectors. Such errors can lead to data visualization artifacts that can easily lead to incorrect conclusions about data, and account for the apparent "undercompensation" previously described for multicolor staining. CONCLUSIONS: There are inescapable errors arising from imperfect measurements, photon-counting statistics, and even data storage methods that contribute both linearly and nonlinearly to a "spreading" of a properly compensated autofluorescence distribution. This phenomenon precludes the use of "quadrant" statistics or gates to analyze affected data; it also precludes visual adjustment of compensation. Most importantly, it is impossible to properly compensate data using standard visual graphical interfaces (histograms or dot plots). Computer-assisted compensation is required, as well as careful gating and experimental design to determine the distinction between positive and negative events. Finally, the use of special staining controls that employ all reagents except for the one of interest (termed fluorescence minus one, or "FMO" controls) becomes necessary to accurately identify expressing cells in the fully stained sample.