Heterochrony in the evolution of Trinidadian guppy offspring size: maturation along a uniform ontogenetic trajectory.

The size and maturity of Trinidadian guppy (Poecilia reticulata) offspring vary among populations adapted to environments of differential predation. Guppy offspring born to low-predation, high-competition environments are larger and more mature than their high-predation ancestors. Here we ask: what specific changes in developmental or birth timing occur to produce the larger, more mature neonates? We collected specimens across the perinatal window of development from five populations and quantified musculoskeletal maturation. We found that all populations undergo similar ontogenetic trajectories in skeletal and muscle acquisition; the only difference among populations is when neonates emerge along the trajectory. The smallest neonates are born with 20% of their skeleton ossified, whereas the largest neonates are born with over 70% of their skeleton ossified. The area of the major jaw-closing muscle is relatively larger in larger offspring, scaling with length as L2.5 The size range over which offspring are birthed among populations sits along the steepest part of the size-maturity relationship, which provides a large marginal increase in fitness for the high-competition female. Because of the functional effects of producing more mature offspring at birth, offspring size may be the first and most critical life-history trait selected upon in highly competitive environments.

Morphological and functional maturity of the oral jaws covary with offspring size in Trinidadian guppies.

Large size of individual offspring is routinely selected for in highly competitive environments, such as in low-predation populations of the Trinidadian guppy (Poecilia reticulata). Large guppy offspring outcompete their smaller conspecifics, but the functional mechanisms underlying this advantage are unknown. We measured jaw kinematics during benthic feeding and cranial musculoskeletal morphologies in neonates and juveniles from five populations of Trinidadian guppy and found that both kinematics and morphologies vary substantially with neonatal size. Rotation at the intramandibular joint (IMJ), but not the quadratomandibular joint (QMJ), increases with size among guppy offspring, from 11.7° in the smallest neonates to 22.9° in the largest neonates. Ossification of the cranial skeleton varies from 20% in the smallest neonates to 90% in the largest. Relative to standard length (SL; jaw tip to caudal fin base distance), the surface area of jaw-closing musculature scales with positive allometry (SL2.72) indicating that muscle growth outpaces body growth. Maximum gape also scales with positive allometry (SL1.20), indicating that larger neonates are capable of greater jaw excursions. These findings indicate that size is not the sole adaptive benefit to producing larger offspring; maturation provides a potential functional mechanism underlying the competitive advantage of large offspring size among Trinidadian guppies.

Career, research involvement, and research fellowship plans of potential psychiatrists.

For this investigation, we used Association of American Medical Colleges survey data to compare the career, research involvement, and research fellowship plans of 532 senior medical students in 1985 intending to specialize in psychiatry with plans of 10,516 students designating other specialty preferences, and discriminant analyses to identify factors associated with psychiatry students' career, research, and fellowship plans. Although a higher percentage of the psychiatry students planned academic or research careers than did their classmates in the other specialties (34.6% vs 27.8%), a lower percentage expected to take a research fellowship (15.4% vs 20.7%). In the multivariate analysis, medical school experience variables such as research, publication, and exposure to a research-oriented environment all were associated with plans for a career in academic medicine or research, exclusive or significant research involvement, and plans to complete a research fellowship.

Research activities of full-time faculty in academic departments of psychiatry.

Using data collected by a 1989 American Psychiatric Association survey of full-time, salaried faculty in departments of psychiatry at US medical schools, we examined the number of faculty engaged in research, their levels of involvement in research, distribution, sources of funding, fields and topics studied, and training. Using a three-level measure of research involvement, we categorized 39.1% of the respondents as "researchers," 36% as "limited commitment researchers," and 25.1% as not involved in research. In a pattern similar to that observed for research funding in other studies, half of the researchers were concentrated in the top 15 of the 116 responding departments. Level of research involvement varied by degree type (joint-program MD/PhDs were most involved), sources of funding, fields, and topics. Among faculty with MDs, having had research experiences in medical school or postdoctoral research training was associated with a higher level of research involvement. The findings underscore the need to expand and improve postdoctoral research training--especially for MDs--and programs to recruit college and medical students into psychiatric research.

Sex differences in rank attainment and research activities among academic psychiatrists.

Data from a survey distributed to all full-time faculty in academic departments of psychiatry were used to examine possible sex differences in research activities and rank attainment among psychiatrists. A total of 1923 psychiatrists responded, 1564 men (81.3%) and 359 women (18.7%). Continuous dependent variables were analyzed by using analyses of covariance with the year graduated from medical school as a covariate. For categorical dependent variables, the sample was divided into four 10-year cohorts based on the year graduated from medical school, and differences between men and women were analyzed with chi 2 tests. Over the entire sample, men were more likely than women to have had research training, to have ever been principal investigators on peer-reviewed grants, to mentor research trainees, to be currently involved in research activities, and to meet defined criteria as a "researcher." Many gender differences remained significant after controlling for seniority and research training. In every cohort, the men had attained higher academic rank than the women. In general, differences in research activity and productivity were most marked in the youngest cohort. To ensure a rich talent pool for psychiatric research, efforts must be made to recruit and support researchers from among the increased number of women in psychiatry.

Professional practice patterns of U.S. psychiatrists.

OBJECTIVE: The authors develop a classification of psychiatric practice based on primary and secondary work settings. METHOD: Data from the 1988-1989 APA Professional Activities Survey were used to characterize seven practice groups: public psychiatrists, public psychiatrists with private secondary work settings, private psychiatric/general hospital psychiatrists, private office practice psychiatrists, private office practice psychiatrists with secondary private psychiatric/general hospital work settings, private office practice psychiatrists with secondary settings other than private hospitals, and psychiatrists in private organized outpatient settings. Psychiatrists primarily in government administrative agencies, medical schools, or nursing homes were among those excluded. Usable data were available from 16,135 psychiatrists (82.8% of the target respondents). RESULTS: The largest groups were private psychiatric/general hospital psychiatrists (19.6%), private office practice psychiatrists with secondary settings other than private hospitals (18.9%), and private office practice psychiatrists with secondary private psychiatric/general hospital work settings (17.4%), followed by public psychiatrists with private secondary work settings (14.5%), private office practice psychiatrists (11.7%), public psychiatrists (11.4%), and psychiatrists in private organized outpatient settings (6.6%). During a typical week, the practice groups varied in the average proportion of their outpatients who received assessments, therapy and medication, therapy and no medication, and medication management. The groups also varied in the mean number of patients they treated each month with affective disorders, schizophrenia, anxiety disorders, and other disorders. CONCLUSIONS: Only about one in 10 clinical psychiatrists is engaged exclusively in office-based private practice, and approximately half of the outpatients treated by the average psychiatrist receive medication. Work setting appears to exert a powerful influence over whom psychiatrists treat and what services they provide. Because a majority of psychiatrists work in more than one setting, most psychiatrists serve a broad range of patients and provide a variety of treatments.

Sex differences in psychiatrists' practice patterns and incomes.

OBJECTIVE AND METHOD: Using data from the APA's 1988-1989 Professional Activities Survey, the authors compared male and female psychiatrists on demographic characteristics, training, practice patterns, and income. RESULTS: In keeping with previous studies' findings, female respondents on the average were younger than male respondents and more likely to have taken a residency or fellowship in child or adolescent psychiatry, worked fewer hours per week, allocated their working hours differently among types of activities, saw fewer patients per week, and worked in somewhat different settings. Multiple regression analysis showed that women had significantly lower mean net annual income than men after the effects of those predictors were statistically controlled. CONCLUSIONS: Differences in age, training, hours worked in specific settings, and numbers of patients do not completely account for the gender gap in psychiatrists' annual incomes.

Psychiatrist and nonphysician mental health provider staffing levels in health maintenance organizations.

OBJECTIVE: This study attempts to determine the ratio of full-time-equivalent psychiatrists to members and that of nonphysician mental health professionals to psychiatrists in staff and group model health maintenance organizations (HMOs), and to compare the psychiatrist-to-member ratio with previous estimates of the required psychiatrist-to-population ratios in fee-for-service and managed care environments. METHODS: The Group Health Association of America (now the American Association of Health Plans) collected data on mental health staffing, enrollments, and other characteristics for 30 staff and group model HMOs. The authors evaluated the number of full-time-equivalent psychiatrists and nonphysician mental health professionals per 100,000 HMO members, and the ratio of full-time-equivalent nonphysician mental health professionals to psychiatrists. RESULTS: The overall mean number of full-time-equivalent psychiatrists and nonphysician mental health professionals per 100,000 members in the responding HMOs was 6.8 and 22.9, respectively. The overall mean ratio of nonphysician professionals to psychiatrists was 4.5. The overall number of psychiatrists per 100,000 members is less than half the requirement estimated by the Graduate Medical Education National Advisory Committee in 1980, which assumed a fee-for-service environment, but it is about 40% to 80% greater than that estimated by other studies under the assumption of a managed care environment. CONCLUSIONS: Although a practice environment dominated by managed care may not require as high a psychiatrist-to-population ratio as a predominantly fee-for-service environment, it may well support a greater number of psychiatrists than previous studies have suggested.

Trends in research in two general psychiatric journals in 1969-1990: research on research.

OBJECTIVE: The authors describe the characteristics of psychiatric research over the past two decades as captured in the articles published by two general psychiatric journals. METHOD: A total of 1,236 articles were drawn from The American Journal of Psychiatry and Archives of General Psychiatry for October through September 1969-1970, 1979-1980, and 1989-1990. Articles were assigned to one of five categories. Research articles were then further categorized as to methodological approach and field of research as well as specific topic areas. Funding sources listed for each research article were also indexed. RESULTS: Over time and in both journals, the percentage and number of research articles have risen, with a concomitant reduction in case reports, opinion papers, and "other" articles. Categories of research design were fairly consistent across time and in both journals. Percentages of articles on specific fields and topics indicated an increasing emphasis on biological studies, especially those in clinical psychobiology, as well as a sharp move away from general categories to a more disorder-specific orientation. Reporting of funding sources has substantially increased. CONCLUSIONS: The large proportion of research articles published in these two important general psychiatric journals reflects editorial policies, changing audience expectations, and the availability of new research tools. Systematic analysis of trends in psychiatric research and other forms of research on research can be useful approaches to assessing the growth and utilization of knowledge in the field, to planning how to most effectively use limited research resources, and to increasing public support for research.

The relationship of postdoctoral research training to current research activities of faculty in academic departments of psychiatry.

OBJECTIVE: This report describes the postdoctoral research training of faculty in departments of psychiatry and relates research training characteristics to current involvement in research. METHOD: Data were taken from a survey of 3,107 doctoral-level faculty in departments of psychiatry at 116 U.S. medical schools. The survey instrument gathered information about faculty members' postdoctoral research training and current research activities and elicited recommendations for research training programs. RESULTS: Of the survey respondents, 34.8% had had some form of postdoctoral research training. Most of those had trained in medical schools or intramural programs of the National Institutes of Health and federal institutes on alcoholism, drug abuse, and mental health. Most funding came from the federal government. Postdoctoral research training was significantly related to greater current research involvement across all degree types--M.D., Ph.D., and M.D.-Ph.D. Length of training was related to level of research involvement for M.D.s and Ph.D.s but not M.D.-Ph.D.s. Although most researchers believed their training programs prepared them for independent research, a smaller proportion of M.D.s than M.D.-Ph.D.s or Ph.D.s responded affirmatively to that question. Researchers were more likely than nonresearchers to consider their training adequate. Respondents rated time with mentor, course work in statistics, and length of training as the most important training program features. Both research training and research activities were concentrated in a relatively few institutions. CONCLUSIONS: These data show the critical importance of both federal support of research training and postdoctoral research training for subsequent research involvement of psychiatric faculty.

A national study of psychiatrists' professional activities.

OBJECTIVE AND METHOD: A mail survey was conducted in 1988-1989 to study the professional activities of U.S. psychiatrists. Data from the 19,431 active respondents are reported. RESULTS: Nineteen percent of the psychiatrists were women, an increase from the 17% reported in 1982. The median age of the respondents was 50 years. Nearly one-third of the respondents expressed interest in each of the following areas of subspecialization: adolescent psychiatry, substance abuse, geriatrics, and consultation-liaison psychiatry. More than one-fifth reported formal fellowship training in child/adolescent psychiatry. The psychiatrists worked an average of 48 hours per week--two-thirds in direct patient care--in an average of 2.3 different settings. The proportion of psychiatrists reporting private practice as their primary work setting showed a marked decline from 53% in 1982 to 45% in 1988. There was an increase from 4% in 1982 to 11% in 1988 in those whose primary work setting was a private psychiatric hospital. The typical caseload was over 60 patients, with roughly half that number seen each week. For inpatients treated, the two most common diagnoses were affective disorders and schizophrenic disorders. In a typical week psychiatrists treated about one-half of their outpatients with individual psychotherapy; three-fifths of these were also treated with medications. The average net income for psychiatrists working 35 hours or more per week was $99,850 for men and $73,174 for women. CONCLUSIONS: Major trends evident from this study are subspecialization, medicalization, privatization, feminization, and organizational diversification.

Clinical staffing in staff- and group-model HMOs.

Analysts frequently have used health maintenance organization (HMO) staffing patterns as a yardstick for estimating national clinical workforce requirements. Based on a nationwide survey of fifty-four staff- and group-model HMOs, the largest sample yet used in an analysis of this type, this DataWatch examines physician-to-member ratios, the use of nonphysician providers, and HMOs' methods of estimating clinical staffing needs. Overall physician staffing ratios and primary care physician staffing ratios closely resemble those reported in previous studies, but they exhibit wide variability and are strongly correlated with HMO size. Although caution should be exercised when using HMO staffing ratios in projections of physician workforce requirements, the ratios described here support projections of a specialty physician surplus.

Sex differences in rank attainment among radiology and internal medicine faculty.

Overall, the percentage of women attaining the ranks of associate professor and professor remains well below the percentage of men in those ranks. Few studies of women in academic medicine have been conducted that might guide the leaders of medical schools and specialty societies in addressing the reasons for this disparity. The Association of American Medical Colleges (AAMC) Faculty Roster System allows comparison of a cohort of faculty at any selected time following their first faculty appointments. This study examined men and women faculty who received their first appointments in the departments of radiology and internal medicine in 1976 and who were still active in 1986. Disparities between men and women in rank attained were apparent in both specialties but were greater in radiology than in internal medicine. Other variables examined include ethnic-racial self-description and teaching, research, patient care, and administrative responsibilities. The authors pose additional research questions requiring information that the Faculty Roster System is not designed to provide.

Curative combination chemotherapy for patients with advanced poorly differentiated carcinoma of unknown primary site.

We have previously reported complete responses and long-term survival following cisplatin-based combination chemotherapy in some patients with advanced poorly differentiated carcinomas of unknown primary site. In order to better define the clinical and pathologic characteristics of the chemotherapy-responsive subgroup, we have reviewed the case histories of our 32 patients who achieved complete response to combination chemotherapy. Initial light microscopic diagnoses were as follows: poorly differentiated carcinoma (23 patients), poorly differentiated adenocarcinoma (eight patients), or poorly differentiated large cell carcinoma (one patient). The median age was 37 years (range, 19-70); 25 of 32 patients were male. All patients had unresectable neoplasms at the time of diagnosis. Twenty-two patients had metastases at two or more locations. In 27 of 32 patients (84%), the predominant site of tumor involvement was either in the mediastinum, retroperitoneum, lymph nodes, or lungs. Six patients were assigned more specific diagnoses at some time during their clinical course on the basis of further pathologic evaluation, additional biopsy material, or autopsy: germinal tumors, two patients; adenocarcinoma of the lung, one patient; carcinoid tumor of the lung, one patient; and malignant melanoma, two patients. Eighteen patients (56%) remain continuously disease free at a median of 77 months following diagnosis and are considered unlikely to recur. All patients with poorly differentiated carcinomas and tumor location in the mediastinum, retroperitoneum, lungs, or lymph nodes should be considered for treatment with intensive cisplatin-containing combination chemotherapy, since some of these patients have potentially curable malignancies.

Predictive validity of specialty choice data from AAMC graduation questionnaire. Association of Medical Colleges.

Several previous studies have used data from the Association of American Medical Colleges' annual graduation survey to address questions about medical students' specialty preferences. Only recently, however, has it become possible to test the validity of these data as indicators of the specialties in which students will actually receive training. Comparisons of 1983 graduation questionnaire data with data on the third-year residencies for the same cohort reveal that the specialty preferences indicated on the questionnaire were good predictors of the residency programs the respondents were in during the third year following graduation.

Relationship of scholarships and indebtedness to medical students' career plans.

Discriminant functions analyses of data from the 1983 survey of senior medical students by the Association of American Medical Colleges showed that the effects of scholarships must be taken into account when assessing the influence of indebtedness on medical students' career choices. Receipt of a federal scholarship, type of medical school attended (public or private), marital status, sex, and receipt of a nonfederal scholarship were found to be more powerful than indebtedness as predictors of whether the students preferred primary care or nonprimary care specialties. Receipt of a federal scholarship, type of school attended, and sex were found to be more powerful than indebtedness as predictors of whether the students preferred private clinical practice, salaried clinical practice in a hospital or clinic, salaried clinical practice in a public agency, or a nonclinical career. Indebtedness was found not to be a predictor of willingness to locate in a socioeconomically deprived area.

Curriculum evaluation, education financing, and career plans of 1983 medical school graduates.

The Association of American Medical Colleges annually gathers data on curriculum evaluation, financing, and career plans from senior medical students through a graduation questionnaire. According to the 1983 survey, a majority of the seniors perceived that an appropriate amount of time was devoted to the various areas of instruction at their institutions. The average indebtedness of the graduates was reported to be increasing, and 84.4 percent reported having medical school debts. Only 13.2 percent of the graduates indicated plans to enter a career in research, although over one-third had some research involvement while in medical school. Those who participated in research activities during medical school were somewhat more likely to plan significant research involvement after graduation than those who were not involved in research in medical school.