Biomedical subjects

A C Leon

Publications and source records attributed to A C Leon.

116 records · Page 7Linked to original sources

PubMedDate not supplied

A dynamic adaptation of the propensity score adjustment for effectiveness analyses of ordinal doses of treatment.

The propensity score adjustment is a method to reduce bias in observational studies. We propose a strategy that involves a novel combination of three data analytic techniques, which adapts the propensity adjustment for additional perturbations of longitudinal, observational studies. First, ordinal logistic regression examines propensity for ordinal doses of treatment. Second, a mixed-model approach incorporates the multiple treatment trials and multiple episodes that are characteristic of chronically ill subjects. Finally, a mixed-effects grouped-time survival model incorporates the propensity score in treatment effectiveness analyses. The strategy that is applied here to an observational study of affective illness can also be used to evaluate the effectiveness of treatments for other chronic illnesses.

Adolescent↗

PubMedDate not supplied

Gate questions in psychiatric interviewing: the case of suicide assessment.

Gate questions are commonly used to shorten structured interviews, by not probing negative responses with more detailed questions. This study quantified cases of aborted suicide attempts that would have been missed, if we had skipped detailed questions following a gate. To accomplish this, we interviewed a random sample of 135 adult psychiatric inpatients concerning their past suicidal behavior. Using our structured interview, subjects were asked a general question about aborted suicide attempts, and then asked method-specific questions regardless of their response to the general "gate" question. Of the seventy subjects who were found to have histories of aborted attempts, 44.3% answered "no" to the gate question. Comparing these "false negative" subjects to "true positives," who had answered "yes" to the gate question and reported bona fide aborted attempts yielded no significant associations with demographics, psychiatric diagnoses, or reported histories of actual suicide attempts. Thus, a large number of subjects with aborted attempts would have been missed if a negative response to the gate question had not been probed. Clinical and reasearch implications generally, as well as implications for suicide assessment, are discussed.

Humans↗

PubMedDate not supplied

Cost effectiveness of screening for clinical trials by research assistants versus senior investigators.

This study evaluates the relationship between interviewer level of experience and the positive predictive value and cost of telephone screening of subjects for randomized clinical trials. This is a previously uninvestigated area. Respondents to advertisements for chronic depression treatment research received brief, semi-structured telephone interviews (N = 347) either by research assistants (RAs) or by a senior investigator (SI). Those who met criteria based on the phone interview were then interviewed in person using the SCID-P. The RAs did not significantly differ from the SI in the proportion of phone screen positives who were also SCID positive or the proportion of phone screen positives who were randomized. While the SI performed phone interviews significantly faster than the RAs, the SI's higher salary generated a phone screening cost per randomized subject 56% more than that of RAs. The results suggest that trained research assistants are more cost effective than senior investigators for initial screening of depressed patients for research protocols. Further studies are needed to determine whether the findings reported would generalize to other research settings or patient populations.

Adult↗

PubMedDate not supplied

Charting patients' course: a comparison of statistics used to summarize patient course in longitudinal and repeated measures studies.

Investigators conducting longitudinal studies of psychiatric illnesses often analyze data based on psychiatric symptom scales that were administered at multiple time points. This study examines the statistical properties of seven indices that summarize patient long-term course. These indices can be used to compare differences between two or more groups or to test for changes in symptoms over time. They may also be treated as outcome measures and correlated with other clinical variables.The performance of each of the seven indices was assessed using data from two large ongoing studies of psychiatric patients: a longitudinal study of affective disorders and a longitudinal study of first-episode psychosis. These two datasets were subjected to bootstrapping techniques in order to calculate both type I error rates and statistical power for each summary statistic. Of the seven indices, Kendall's tau performed the best as a measure of patients' symptom course. Kendall's tau appears to offer more statistical power to detect change in course, yet its average type I error rate was comparable to the other indices.

Adult↗

PubMedDate not supplied

Childhood trauma as a correlate of lifetime opiate use in psychiatric patients.

Associations have been reported between childhood sexual and/or physical abuse and adult substance abuse in general. This study investigated the relationship between childhood abuse and opiate use in particular among 763 consecutively admitted psychiatric inpatients. Patients were interviewed about demographic information, alcohol and drug use, and history of interpersonal violence. Opiate users were 2.7 times more likely to have a history of childhood sexual and/or physical abuse than nonopiate users, after controlling for diagnostic and sociodemographic variables. Opiate use was higher among those reporting physical abuse alone (24.1%) or both physical and sexual abuse (27%) than among those reporting sexual abuse alone (8.8%). Implications of these findings are discussed.

Adolescent↗

PubMedDate not supplied

Qualitative differences in manic symptoms during mixed versus pure mania.

Previous studies have compared demographic and clinical-outcome features of bipolar patients with mixed or pure mania. However, little is known about the potential differences in the nature and extent of manic symptoms in mania either with or without an accompanying depression. This study examined DSM-III-R manic symptoms in a cohort of 183 bipolar I inpatients hospitalized for mixed mania (diagnosed by broad or narrow criteria) or pure manic episodes. Inpatient charts were reviewed to determine the presence of individual affective symptoms. The results indicate that clinicians were more likely to diagnose a pure mania from the beginning to end of an episode than to diagnose a mixed mania from its beginning to end. Mixed-manic patients had significantly fewer manic symptoms than pure manic patients. Grandiosity, euphoria, pressured speech, and a decreased need for sleep were more prevalent during pure versus mixed mania. Grandiosity and a diminished need for sleep were especially notable during pure mania compared with mixed mania as defined by narrow criteria for mixed states. The observed differences in manic symptom profiles between mixed and pure mania may aid in the clinical assessment of dysphoric states among bipolar patients. The data also lend support to the use of broad diagnostic criteria for defining mixed mania as an entity phenomenologically distinct from pure mania.

Acute Disease↗

PubMedDate not supplied

A profile of homicides on the streets and in the homes of New York City.

Although prior research has found that homes containing firearms and illicit drug and ethanol users are more likely to be the scene of a homicide than homes that do not contain these elements, the authors studied homicides on the streets as well as in homes so as to assess the role of firearms, cocaine, and ethanol in both settings. Using the files of the Chief Medical Examiner, the authors reviewed all 4,468 homicides occurring in New York City in 1990 and 1991. The most frequent places of occurrence were the streets and other outdoor places (49.6 percent) and the victims' homes (19.3 percent). Firearms were the cause of death for 49.6 percent of homicides in the home and 80.3 percent of those on the streets. Use of cocaine and ethanol was found more frequently among victims killed on the streets than those killed at home. In addition, victims killed on the streets were more likely to be male, ages 15-24 years, and African American. Further research in regard to prevention and intervention strategies is needed, keeping in mind the different patterns of homicide on the streets compared with those occurring in other settings.

Adolescent↗

PubMedDate not supplied

Impact of screening for mental health concerns on health service utilization and functional status in primary care patients.

BACKGROUND: Mental health concerns are common in primary care patients and are often inadequately addressed by primary care physicians. OBJECTIVE: To assess the impact of screening for mental disorders in internal medicine patients. METHODS: Randomly selected patients (n = 358) visiting physicians in 2 firms of an urban academic internal medicine clinic were screened for mental disorders using the 16-item Symptom-Driven Diagnostic System for Primary Care (Upjohn Co, Kalamazoo, Mich) first-stage screening questionnaire. In the experimental firm, physicians received the screening results and then administered second-stage diagnostic modules. In the control firm, physicians were not notified of the results of the screening questionnaire. Baseline and 3-month function were assessed using the SF-36 Health Survey, the Zung Self-Rating Depression Scale, and the Sheehan Patient-Rated Anxiety Scale. Patient satisfaction and health care utilization were also assessed by questionnaire at baseline and after 3 months. RESULTS: Patients screening positively for any mental disorder (n = 238, 66.5%) had markedly lower baseline functional status than those screening negatively (P < .05 on all 8 SF-36 Health Survey subscales) and more total (+/- SD) outpatient visits over 3 months (4.5 +/- 5.5 vs 2.5 +/- 2.6 visits, P = .001). Among patients who screened positively, functional outcomes and patient satisfaction were similar in experimental and control groups; mean utilization (+/- SD) was lower in the experimental group (3.7 +/- 3.9 vs 5.3 +/- 6.7 total outpatient visits at 3 months, P = .06; 0.9 +/- 1.5 vs 2.1 +/- 3.7 visits to non-mental health specialists, P = .003; 0.2 +/- 0.5 vs 0.4 +/- 0.9 x-ray films per patient, P = .01). The follow-up response rate was 286 (79.9%) of 358 patients. CONCLUSIONS: The 16-item first-stage Symptom-Driven Diagnostic System for Primary Care screening questionnaire for mental disorders can identify primary care patients who are at risk for lower functional status and higher utilization. Use of the Symptom-Driven Diagnostic System for Primary Care second-stage diagnostic modules in patients who screened positively for mental disorders was associated with lower utilization rates but had no impact on functional outcome or patient satisfaction after 3 months.

Female↗