Estimating fecundability from data on waiting times to first conception

"This article tests assumptions invoked in the demographic literature to estimate the population distribution of fecundability from data on waiting times to first conception. In continuous time, the key assumption is that waiting times are realizations from a mixture of exponentials distribution. In discrete time, the key assumption is that waiting times are realizations from a mixture of geometrics distribution. The [U.S.] Hutterite data analyzed by Sheps (1965) are consistent with this assumption. Various models, however, have one representation in mixture of exponentials form. A fundamental identification problem plagues the conventional estimation procedure. Our analysis calls into question the conventional practice of checking model specification by using goodness-of-fit tests. The practical importance of the identification problem in duration models is demonstrated."     

CONTEXT EFFECTS FOR CENSUS MEASURES OF RACE AND HISPANIC ORIGIN

This paper reports on the results of a split-ballot experimentconducted in 1987 to test alternative versions of the decennialcensus long form. Two forms were randomly assigned and self-administeredin group sessions involving a total of 515 respondents. Theorder of race and Hispanic origin items was experimentally manipulated.The standard long form asks race, then Hispanic origin. Theexperimental form reversed the order of the items in order toreduce perceived redundancy, and to create a more restrictedframe of reference for the race item. The objectives of thecontext manipulation were (1) to reduce item nonresponse forthe Hispanic origin item, and (2) to reduce reporting of "Otherrace" by Hispanics in the race item. Objective (1) was met.Objective (2) was met for Hispanics born in a U.S. state, butnot for immigrants. The results are interpreted as reflectinga process of acculturation that affects how Hispanic respondentsapply U.S. racial categories "white" and "black" in the census.     

The medical examiner and deaths in the hospital setting

There has been a perceived increase in the number of medical negligence claims in recent years. The modern metropolitan medical examiner is increasingly called upon to deal with numerous medical, legal, social, and ethical issues. Nowhere is the role of the medical examiner more important than in the investigation of deaths related to surgical, diagnostic, anesthetic, or therapeutic procedures. Medical examiners have an important role in the investigative process. Through utilization of the offices and services of the medical examiner, questions raised by families, physicians, and other hospital employees may be satisfactorily answered a priori, and litigation may therefore be averted.     

Strategically integrating hospital/home care services for improved profitability

Because hospitals and home health agencies have been predominantly separate organizations, coordination of their efforts has not been optimized. However, with the recent proliferation of hospital-based home health agencies, opportunities to integrate these health care service delivery systems have increased. Bethesda Memorial Hospital, Boynton Beach, Fla., is a 362-bed not-for-profit community hospital with a Medicare-certified home health agency organized as a department of the hospital. Until recently, the home health agency was generally perceived as a separate entity whose services were distinct from hospital services. Progress toward integration of hospital and home care services was given impetus through collaboration of the home health agency administrator and a newly appointed director of medical affairs who was given the responsibility as medical director of the home health agency. A prime responsibility of the director of medical affairs was to reduce length of stay and hospital costs through appropriate resource management.     

The appointment-keeping habits of managed care patients

Among the controversies surrounding the provision of health care in a managed care environment is the belief that patients, because they have no particular allegiance to a single physician, are more casual in regard to their keeping appointments. To test this proposition, the authors conducted a study at a California independent practice association, comparing the habits of managed care patients with those of other types of patients. The findings, although based on a limited sample, suggest that managed care patients do indeed have a greater tendency to be appointment no-shows.