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PubMed1997

Enhancing motivation to reduce the risk of HIV infection for economically disadvantaged urban women.

This research evaluated a motivation-based HIV risk reduction intervention for economically disadvantaged urban women. Participants completed a survey that assessed HIV-related knowledge, risk perceptions, behavioral intentions, sexual communication, substance use, and risk behavior. A total of 102 at-risk women (76% African American) were randomly assigned to either the risk reduction intervention or to a waiting list. Women were reassessed at 3 and 12 weeks. Results indicated that treated women increased their knowledge and risk awareness, strengthened their intentions to adopt safer sexual practices, communicated their intentions with partners, reduced substance use proximal to sexual activities, and engaged in fewer acts of unprotected vaginal intercourse. These effects were observed immediately, and most were maintained at follow-up.

Adolescent↗
PubMed2004

Factors influencing levels of 17-hydroxyprogesterone in very low birth weight infants and the relationship to death and IVH.

OBJECTIVES: 17-Hydroxyprogesterone, an intermediary hormone in cortisol synthesis, has been shown to be elevated in premature infants. However, the relationship between levels of 17-hydroxyprogesterone with death and intraventricular hemorrhage has not been extensively explored. The objective of this study was to determine the factors influencing 17-hydroxyprogesterone and determine if there is an association between intraventricular hemorrhage, mortality, and levels of 17-hydroxyprogesterone in a population of very low birth weight infants. STUDY DESIGN: Cohort study of very low birth weight infants cared for at a single level 3 NICU during a 1-year period from July 2001 to July 2002. Infants had a minimum of one screen for 17-hydroxyprogesterone and one cranial sonogram. 17-Hydroxyprogesterone was measured on the fifth day of life and at 2 to 4 weeks of life as part of the State of Delaware Newborn Screening Program. Statistical analysis included chi(2), Pearson correlation, multiple-linear regression, and logistic regression. RESULTS: Levels of 17-hydroxyprogesterone were higher at the time of the first screen compared to the second screen (28.3+/-25.6 vs 17.0+/-18.0 ng/ml, p=0.01), respectively. After controlling for potential confounding variables, gestational age, T(4), and prenatal steroids were all independently associated with 17-hydroxyprogesterone. However, logistic regression analysis showed no association between a 1 log increase in levels of 17-hydroxyprogesterone with the outcomes of death (odds ratio 1.8, 95% CI 0.6 to 5.6), severe IVH (0.7, 0.3 to 1.7), and death and/or severe intraventricular hemorrhage (0.9, 0.4 to 2.1). CONCLUSIONS: In our population of very low birth weight infants, low gestational age, low T(4), and prenatal steroids were all associated with an elevation in levels of 17-hydroxyprogesterone. High levels of 17-hydroxyprogesterone were not associated with death and/or severe IVH. Our data indicate that factors such as gestational age and antenatal steroids must be considered when interpreting 17-hydroxyprogesterone results from newborn screening.

17-alpha-Hydroxyprogesterone↗
PubMed2004

Apnea is associated with neurodevelopmental impairment in very low birth weight infants.

OBJECTIVE: To determine whether apnea in preterm infants is associated with abnormal neurodevelopmental outcome. METHODS: We determined the number of days that apnea and bradycardia spells were noted by the nursing staff, during the initial hospitalization of 175 preterm infants of less than <1250 g birth weight or <32 weeks gestation who had been enrolled in the follow-up program of the Royal Victoria Hospital. Multiple logistic and multiple linear regression models were constructed to determine the relationships between apnea days and neurodevelopmental impairment at 3 years of age, after correcting for gestation, sex, intrauterine growth restriction, intraventricular hemorrhage, periventricular leukomalacia, pre- and postnatal steroids, and maternal education. RESULTS: A total of 41 infants had neurodevelopmental impairment (Bayley MDI or PDI <70, cerebral palsy or blindness). By multiple logistic regression, an increasing number of days on which at least one apnea occurred, "total apnea days", and male sex were significantly associated with increasing probability of neurodevelopmental impairment, p<0.01, the sum of days of assisted ventilation and apnea days occurring after extubation was also associated with impairment in a separate regression model, p<0.001. Lower MDI at 3 years was significantly associated with postnatal steroid use, p=0.004. Lower PDI was associated with increasing apnea days, male sex, and postnatal steroid use, p<0.001. Functional impairment (a score on any one of the four dimensions of the Vineland scale <70), found in 17% of the infants, was associated with increasing apnea days, p<0.05. Caffeine treatment was not independently associated with any outcome. CONCLUSION: An increasing number of days that apnea was recorded during hospitalization was associated with a worse outcome. Among the potential explanations for this finding is the possibility that multiple recurrent hypoxic and bradycardic spells may cause brain injury.

Apnea↗
PubMed1999

Etiological aspects on craniofacial morphology in twins with cleft lip and palate.

The craniofacial morphology of 39 Finnish twin pairs concordant or discordant for cleft of the lip (CL), unilateral cleft lip and palate (UCLP), or cleft palate only (CP) was studied by means of lateral cephalometric radiographs. The intrapair differences between various cleft and twin subgroups were compared by means of univariate analysis; multivariable analysis of cleft discordant pairs and the variance components were estimated with the TWINAN program. Larger values for intrapair differences were found, especially in linear measurements in older twin pairs. Heritability estimates for the cranial base measurements and, to a lesser extent, for the mandibular measurements were high. Comparisons on the basis of cleft type revealed more differences between twin pairs when clefting was more severe. Concordant and discordant CP twin pairs showed similarity in their intrapair craniofacial morphology, indicating that surgery seemed to have no major effect on their craniofacial morphology. A similar comparison in discordant UCLP showed that, in addition to clefting itself, external factors, i.e., the repaired cleft's direct effects on craniofacial morphology, have a strong influence on craniofacial morphology, especially in the maxillas of the UCLP twins. The craniofacial morphology in these Finnish twins supports the hypothesis of different genetic behavior for cleft lip and cleft lip and palate (CL(P)) and CP in Finland.

Adolescent↗
PubMed1999

The influence of gatekeeping and utilization review on patient satisfaction.

OBJECTIVE: To examine the influence of utilization review and denial of specialty referrals on patient satisfaction with overall medical care, willingness to recommend one's physician group to a friend, and desire to disenroll from the health plan. DESIGN: Two cross-sectional questionnaires: one of physician groups and one of patient satisfaction. SETTING: Eighty-eight capitated physician groups in California. PARTICIPANTS: Participants were 11,710 patients enrolled in a large California network-model HMO in 1993 who received care in one of the 88 physician groups. MEASUREMENTS AND MAIN RESULTS: Our main measures were how groups conducted utilization review for specialty referrals and tests, patient-reported denial of specialty referrals, and patient satisfaction with overall medical care. Patients in groups that required preauthorization for access to many types of specialists were significantly (p </=.001) less satisfied than patients in groups that had few preauthorization requirements, even after adjusting for patient and other group characteristics. Patients who had wanted to see a specialist in the previous year but did not see one were significantly less satisfied than those who had wanted to see a specialist and actually saw one (p <.001). In addition, patients who did not see a specialist when desired were more likely to want to disenroll from the health plan than patients who saw the specialist (40% vs 18%, p </=.001) and more likely not to recommend their group to a friend (38% vs 13%, p </=.001). CONCLUSIONS: Policies that limited direct access to specialists, and especially denial of patient-desired referrals, were associated with significantly lower patient satisfaction, increased desire to disenroll, and lower likelihood of recommending the group to a friend. Health plans and physician groups need to take these factors into account when designing strategies to reduce specialty care use.

Adolescent↗
PubMed2002

Managed care, primary care, and the patient-practitioner relationship.

OBJECTIVES: This study examines how specific attributes of managed health plans influence patients' relationships with their primary care practitioners (PCPs) and determines whether these effects are mediated by access to, continuity with, or perceived choice of PCPs. DESIGN, SETTING, PATIENTS: The data source was the nationally representative 1996/97 Community Tracking Study Household Survey (cumulative response rate 65%). The study population (N = 19,415) was composed of 18- to 64-year-old adults whose most recent visit in the past 12 months was made to their primary care delivery site. MAIN OUTCOME MEASURE: Patients' ratings of their interpersonal relationships with their PCPs as measured by a 7-item scale. RESULTS: Gatekeeping arrangements that require patients to select a primary care physician or obtain authorization for specialty referrals were associated with lower ratings of the patient-PCP relationship. Health plan use of a provider network had no effect on the patient-PCP scale score. Although there were no significant differences across any insurance payer categories, uninsured adults rated their relationships with PCPs as significantly poorer than did their insured counterparts. Shorter office waits, having a specific clinician at the primary care site, better perceived choice of PCPs, and a longer duration of relationship with the primary care practitioner were associated with higher ratings of the patient-PCP relationship. Perceived choice of primary care practitioners, but not access to or continuity with PCPs, attenuated some of the negative effects of gatekeeping arrangements on patients' relationships with their primary care practitioners. CONCLUSIONS: Managed health plans that loosen restrictions on provider choice, relax gatekeeping arrangements, or promote access to and continuity with PCPs, are likely to experience higher patient satisfaction with their primary care practitioner relationships. Lack of health insurance impedes the development of patients' relationships with their primary care practitioners.

Adolescent↗
PubMed2005

Trends in the quality of care and racial disparities in Medicare managed care.

BACKGROUND: Since 1997, all managed-care plans administered by Medicare have reported on quality-of-care measures from the Health Plan Employer Data and Information Set (HEDIS). Studies of early data found that blacks received care that was of lower quality than that received by whites. In this study, we assessed changes over time in the overall quality of care and in the magnitude of racial disparities in nine measures of clinical performance. METHODS: In order to compare the quality of care for elderly white and black beneficiaries enrolled in Medicare managed-care plans who were eligible for at least one of nine HEDIS measures, we analyzed 1.8 million individual-level observations from 183 health plans from 1997 to 2003. For each measure, we assessed whether the magnitude of the racial disparity had changed over time with the use of multivariable models that adjusted for the age, sex, health plan, Medicaid eligibility, and socioeconomic position of beneficiaries on the basis of their area of residence. RESULTS: During the seven-year study period, clinical performance improved on all measures for both white enrollees and black enrollees (P<0.001). The gap between white beneficiaries and black beneficiaries narrowed for seven HEDIS measures (P<0.01). However, racial disparities did not decrease for glucose control among patients with diabetes (increasing from 4 percent to 7 percent, P<0.001) or for cholesterol control among patients with cardiovascular disorders (increasing from 14 percent to 17 percent; change not significant, P=0.72). CONCLUSIONS: The measured quality of care for elderly Medicare beneficiaries in managed-care plans improved substantially from 1997 to 2003. Racial disparities declined for most, but not all, HEDIS measures we studied. Future research should examine factors that contributed to the narrowing of racial disparities on some measures and focus on interventions to eliminate persistent disparities in the quality of care.

Aged↗
PubMed2003

Predicting academic success in the first year of chiropractic college.

PURPOSE: To determine if any existent preadmission academic or personal variables predict academic success in the first year of the Palmer College of Chiropractic West (PCCW) program. PARTICIPANTS: One hundred ninety-two students at PCCW who had completed the first year of the program. METHODS: One-way analysis of variance and stepwise linear multiple regression. RESULTS: Men had a significantly higher mean matriculating grade point average (MatGPA) than women, but no such relationship existed in the cumulative year-1 GPA (Y1GPA). There was no statistically significant difference in MatGPA for students possessing a degree compared to those without a degree, but degree-holding students had a significantly higher Y1GPA. There was no statistically significant difference in MatGPA for students born in English-speaking countries compared to students born in non-English-speaking countries, but those born in English-speaking countries had a significantly higher Y1GPA. MatGPA, physics GPA, and chemistry GPA provided the strongest regression model, eliciting an R(2) value of 0.327. CONCLUSIONS: Student characteristics on entering PCCW may help predict student performance in the first academic year. A relatively strong and statistically significant prediction model for Y1GPA (R(2) = 0.327) exists for PCCW. Used in conjunction with other available empirical data, this regression model may allow the institution to make more informed decisions when selecting students for admission.

Achievement↗
PubMed2000

Optimizing reduced-space sequence analysis.

MOTIVATION: Dynamic programming is the core algorithm of sequence comparison, alignment and linear hidden Markov model (HMM) training. For a pair of sequence lengths m and n, the problem can be solved readily in O(mn)time and O(mn)space. The checkpoint algorithm introduced by Grice et al. (CABIOS, 13, 45--53, 1997) runs in O(Lmn)time and O(Lm(L) square root of n)space, where L is a positive integer determined by m, n, and the amount of available workspace. The algorithm is appropriate for many string comparison problems, including all-paths and single-best-path hidden Markov model training, and is readily parallelizable. The checkpoint algorithm has a diagonal version that can solve the single-best-path alignment problem in O(mn)time and O(m + n)space. RESULTS: In this work, we improve performance by analyzing optimal checkpoint placement. The improved row checkpoint algorithm performs up to one half the computation of the original algorithm. The improved diagonal checkpoint algorithm performs up to 35% fewer computational steps than the original. We modified the SAM hidden Markov modeling package to use the improved row checkpoint algorithm. For a fixed sequence length, the new version is up to 33% faster for all-paths and 56% faster for single-best-path HMM training, depending on sequence length and allocated memory. Over a typical set of protein sequence lengths, the improvement is approximately 10%.

Algorithms↗
PubMed1990

HCABAND: a computer program for the 2D-helical representation of protein sequences.

A BASIC program, HCABAND, is described which is used to convert the linear amino acid sequence of proteins into a word processor-readable file to generate the 2D-helical representation required for hydrophobic cluster analysis. The user can specify the width of the plot and can use the word processor macro-commands to facilitate visual inspection of the plots. The plots can be easily stored on diskettes, mixed with text and printed. HCABAND features are generally applicable and can be implemented on virtually any microcomputer.

Amino Acid Sequence↗
PubMed1985

Automated data processing for chromatographic assay method validations.

A set of computer programs has been developed for the automated transfer, storage, and processing of data related to chromatographic pharmaceutical assay method validations. These programs calculate and report statistical parameters relating to the resolution, linearity of response, and precision of an assay method based upon peak width, retention time, and integration data provided by a commercial chromatographic data system. Utilization of an interface between the data system and a microcomputer minimizes manual handling of all data. Techniques and equations used in the development of the software are described, and an application to the validation of a high performance liquid chromatographic assay method for a bulk drug substance is demonstrated.

Chromatography, High Pressure Liquid↗
PubMed2000

Differences in physician utilization between Aboriginal and non-Aboriginal children.

OBJECTIVE: In the present study, we examined the factors affecting Aboriginal children's visits to a medical practitioner and compared them with non-Aboriginal children. METHODS: We selected five Aboriginal communities and four neighbouring non-Aboriginal communities, and conducted a door-to-door survey, covering all children born after 1983. Of an initial sample of 1013 children, 896 (response rate 89.92% for non-Aboriginal children and 85.87% for Aboriginal children) completed the questionnaire for analysis. RESULTS: In all, 896 children of non-mixed lineage with an age range of 0-12 years were collected into the study, including 316 Aborigines and 580 non-Aborigines. A higher percentage of non-Aboriginal children had more national health insurance coverage than Aboriginal children. The ratio of parents using the services of an out of community medical practitioner when their children were sick was higher for Aboriginal parents than for non-Aborigines. Medical injection frequency was higher in Aboriginal children. Linear regression was used to examine the factors affecting the frequency of physician utilization in the preceding month. CONCLUSION: A lower national health insurance coverage rate, and a higher rate of intramuscular injections for Aboriginal children plus difficulties in access to medical resources due to travel time and travel distance are still major problems for the Aborigines.

Child↗
PubMed2005

Bicycle helmet use in Sweden during the 1990s and in the future.

This paper describes how the use of bicycle helmets in Sweden has changed for different categories of cyclists from 1988 to 2002, and it also estimates future trends in voluntary wearing of bicycle helmets up to the year 2010. Observational studies of the use of bicycle helmets were conducted once a year from 1988 to 2002 at 157 sites in 21 cities. The subjects observed were children cycling to school (average n = 5471/year) and in their free time (average n = 2191/year), and adults cycling to workplaces and on public bike paths (average n = 29 368/year). The general trend in helmet use from 1988 to 2002 was determined by linear regression analysis, and the results were also employed to estimate future helmet wearing for the period 2003-2010. Differences in helmet use according to gender and size of city were analysed by chi-square tests. From 1988 to 2002, all categories of cyclists showed an upward trend in helmet use (p < 0.01, p < 0.001). Helmet wearing increased from about 20 to 35% among children (< or =10 years) cycling during free time, from approximately 5 to 33% among school children, and from around 2 to 14% in adults. Total average helmet use rose from about 4 to 17%. However, during the last 5 years of the study period (1998-2002), none of the categories of cyclists studied showed an upward trend in helmet wearing. It is estimated that approximately 30% of cyclists will wear helmets voluntarily by the year 2010, if helmet promotion activities are continued at the same level as previously. The results suggest that Sweden will probably not reach its official goal of 80% helmet use unless a national bicycle helmet law is passed.

Adolescent↗
PubMed1993

Improved alignment of weakly homologous protein sequences using structural information.

Protein sequence alignments can be improved when at least one of the proteins to be aligned has a known 3-D structure. In this work, geometrical constraints extracted from the target fold are evaluated in independent units that deal with complementary structural features. This information is used to set up mutation tables specific to the locally observed structural environments. The resulting partial evaluations are then combined linearly into a global function which is optimized by dynamic programming. Eventually, a score based on tertiary interactions can be used as a selection criterion to discriminate among a set of suboptimal alignments. The relevance of the scores given by each unit is tested on a representative set of protein families. Finally, a method for combining the different scores is described and its efficiency is evaluated on a few pairs of weakly homologous proteins.

Algorithms↗
PubMed1998

Casemix adjustment of managed care claims data using the clinical classification for health policy research method.

OBJECTIVES: The objective of this study was to explore the use of the Clinical Classification for Health Policy Research (CCHPR) as a casemix adjustment method for examining physician practice patterns. METHODS: The data source was 2 years of administrative claims from an 86,000 member health maintenance organization in southeastern Michigan. The CCHPR version 2 algorithm, which is in the public domain, was used to assign each claim to one of 260 clinical categories. CCHPR and age-sex categories were used as explanatory variables in multiple linear regression models with approved claims payments in dollars as the outcome variable. Regressions were performed retrospectively for 1994 and 1995, and with 1994 claims' history to predict 1995 utilization. Similar regressions were performed with age-sex categories alone, and also with the ambulatory diagnostic groups. RESULTS: The adjusted R2 value of the retrospective regression models for total approved dollars was 0.42 for both study years when CCHPR categories were used. In contrast, age-sex explanatory variables alone achieved an R2 of 0.02. CONCLUSIONS: The CCHPR method appears to be a promising tool to understand variability in physician resource utilization in managed care.

Adult↗
PubMedDate not supplied

Ethical conflict in nurse practitioners and physician assistants in managed care.

BACKGROUND: More patients are receiving healthcare services from nurse practitioners (NPs) and physician assistants (PAs). These providers are likely to be confronted with a variety of ethical issues as they balance quality care with their patients' rising cost concerns. However, very little is known about the ethical conflicts and causes of these conflicts experienced by these clinicians in their daily practice. OBJECTIVE: To identify ethical concerns and conflicts NPs and PAs encounter related to managed care in the delivery of primary care to patients and the factors that influence ethical conflict. METHODS: A cross-sectional self-administered mailed questionnaire was sent to 3,900 NPs and PAs randomly selected from primary care and primary care subspecialties in the United States (adjusted response rate, 50.6%). Respondents were surveyed on ethical issues and concerns, ethics preparedness, and ethical conflict. Bivariate and multiple linear regression analyses were used to evaluate predictors of ethical conflict. RESULTS: Insurance constraints were reported to have interfered with the ability to provide quality patient care by 72% of respondents, with 55.3% reporting daily to weekly interferences. Nearly half of respondents (47%) have been asked by a patient to mislead insurers to assist them in receiving care. A perceived obligation to advocate for patients, even if it means exaggerating the severity of a patient's condition, was the single most significant predictor of ethical conflict, explaining 25% of the variance. DISCUSSION: NPs and PAs are experiencing ethical conflict often associated with their perceived professional obligations to advocate for patients. Being well-prepared in ethics and having sufficient professional independence help clinicians balance the ethical complexities and demands of meeting patients' needs within a constrained healthcare system.

Adult↗
PubMed1997

Insurance type and satisfaction with medical care among HIV-infected men.

Patient satisfaction is a valuable indicator of the quality of medical care. We assessed the impact of type of health insurance on satisfaction with seven aspects of medical care among 593 HIV-infected men without AIDS, drawn from three sites in San Francisco, California and Denver, Colorado. After adjustment for site of medical care, patient age, race, income, education, and CD4 lymphocyte count, there were few differences in satisfaction between men with fee-for-service and those with managed care insurance. Men with fee-for-service insurance were significantly more satisfied with their interpersonal relations with their clinicians (p = 0.01) but less satisfied with their finances (p = 0.0001) than persons with managed care. Uninsured men were significantly less satisfied with several aspects of care than insured persons. There were no significant differences in satisfaction between men with managed care and those with public insurance. HIV-infected persons who have a choice of insurance should carefully weigh their options, recognizing the implicit trade-offs between types of insurance. Those who choose fee-for-service insurance can expect to be more satisfied with interpersonal relations with their medical providers but less satisfied with financial aspects of their plans. Efforts to address the low satisfaction of uninsured persons are needed.

Adult↗
PubMed2003

Race/ethnicity, language, and patients' assessments of care in Medicaid managed care.

OBJECTIVE: Consumer assessments of health care provide important information about how well health plans and clinicians meet the needs of the people they serve. The purpose of this study was to examine whether consumer reports and ratings of care in Medicaid managed care vary by race/ethnicity and language. DATA SOURCES: Data were derived from the National CAHPS Benchmarking Database (NCBD) 3.0 and consisted of 49,327 adults enrolled in Medicaid managed care plans in 14 states in 2000. DATA COLLECTION: The CAHPS data were collected by telephone and mail. Surveys were administered in Spanish and English. The response rate across plans was 38 percent. STUDY DESIGN: Data were analyzed using linear regression models. The dependent variables were CAHPS 2.0 global rating items (personal doctor, specialist, health care, health plan) and multi-item reports of care (getting needed care, timeliness of care, provider communication, staff helpfulness, plan service). The independent variables were race/ethnicity, language spoken at home (English, Spanish, Other), and survey language (English or Spanish). Survey respondents were assigned to one of nine racial/ethnic categories based on Hispanic ethnicity and race: White, Hispanic/Latino, Black/African American, Asian/Pacific Islanders, American Indian/Alaskan native, American Indian/White, Black/White, Other Multiracial, Other Race/Ethnicity. Whites, Asians, and Hispanics were further classified into language subgroups based on the survey language and based on the language primarily spoken at home. Covariates included gender, age, education, and self-rated health. PRINCIPAL FINDINGS: Racial/ethnic and linguistic minorities tended to report worse care than did whites. Linguistic minorities reported worse care than did racial and ethnic minorities. CONCLUSIONS: This study suggests that racial and ethnic minorities and persons with limited English proficiency face barriers to care, despite Medicaid-enabled financial access. Health care organizations should address the observed disparities in access to care for racial/ethnic and linguistic minorities as part of their quality improvement efforts.

Adult↗