The impact of condom availability [correction of distribution] in Seattle schools on sexual behavior and condom use.

OBJECTIVES: Ten Seattle high schools made condoms available through vending machines, baskets in school clinics, or both. This study measured the number of condoms that students obtained and subsequent changes in sexual behavior and condom use. METHODS: Schoolwide surveys were administered in spring 1993 and in spring 1995, before and during the condom availability program. These data were compared with data from nationally representative surveys administered at the same time. RESULTS: Seattle students obtained an average of 4.6 condoms per year, the vast majority from baskets and very few from vending machines. Relative to the national samples, the percentage of Seattle students who had ever had sex remained stable after the program began; current sexual activity decreased significantly; and the percentage of sexually experienced students who used a condom the last time they had sex decreased significantly, particularly in the 5 schools with baskets of condoms in clinics. CONCLUSIONS: Making condoms available in Seattle schools enabled students to obtain relatively large numbers of condoms but did not lead to increases in either sexual activity or condom use.

Nonuniform image representation in area-of-interest systems.

This paper is concerned with image representation by data distributed nonuniformly and in particular with a representation scheme suitable for "area-of-interest" imaging. The class of signals under consideration, whose information density varies with position, can be represented according to a nonuniform sampling scheme. Position-varying projection operators are presented as simple low-pass filtering operations in a Fourier-like domain. Sequential projections are used for pyramidal representation of nonuniformly sampled images. It is shown that irregular random sampling, prevents, under certain mild restrictions, aliasing effects.

Second-order bounds on the domain of attraction and the rate of convergence of nonlinear dynamical systems and neural networks.

We present a method for analyzing the convergence properties of nonlinear dynamical systems yielding second-order bounds on the domain of attraction of an asymptotically stable equilibrium point and on the time of convergence in the estimated domain. We show that under certain conditions on the system, there exists an analytic solution to the corresponding optimization problem. The method is applied in analyzing the dynamics of a neural network model.

Insurance, income, and access to ambulatory care in King County, Washington.

OBJECTIVES: We studied simultaneous effects of income and insurance on access measures in an indigent population, focusing on Medicaid and the marginal effects of increasing income. METHODS: Surveys were distributed in waiting rooms of county clinics and welfare offices. Models examined insurance (private, Medicaid, or none), income (to twice the poverty level), single-parent status, age, gender, and presence of a regular source of care; first-order interactions were evaluated. RESULTS: In terms of ease of access, postponing care, and having a regular source of care, uninsured respondents fared worst and Medicaid recipients were at an intermediate level. However, relative to those with private insurance, Medicaid recipients had four times the odds, and uninsured respondents twice the odds of being denied care. Income had no consistent effect; however, older, poorer people may have greater problems. For preventive services, income was significant, while differences between Medicaid and private insurance were generally not significant. CONCLUSIONS: Except for denial of care, access for indigent people is improved by Medicaid but remains worse than the access of those with private insurance. Income had variable effects, but support for income criteria used for public insurance eligibility was not found.

A comparison of users and nonusers of a school-based health and mental health clinic.

This study compares student health and mental health knowledge, behavior, and access to services for adolescents who used and did not use a school-based health and mental health clinic. Data were collected as part of an anonymous, self-administered survey completed by all students in a school housing a clinic that had been in operation for a school year. Comparisons of clinic users and nonusers revealed differences in health- and mental health-related knowledge and behavior and access to needed care. The clinic was found to be serving adolescents at high risk for a variety of psychosocial problems (e.g., drug use, depression, dropout).

Marketing public health services.

Marketing techniques that have proved their worth in the private sector can be applied successfully to public and non-profit agencies. This paper explores the applicability of marketing practices to public health departments. Many health departments are now facing pressures to re-examine and update roles in light of changes in morbidity and mortality and changes in consumer wants and needs. Marketing techniques can be helpful in evaluating services systematically in regard to consumer needs and preferences, planning and improving services to meet those needs and increasing agency visibility and credibility. One health department's experience in using marketing techniques is shared. Problems faced, solutions developed and recommendations for future activities are discussed.