Editor’s Note: This article was written by Jacqueline Dunbar-Jacob, Ph.D., R.N., Director of the Center for Research in Chronic Disorders (CRCD), School of Nursing, University of Pittsburgh. Her colleagues also working on this project at CRCD include Judy Erlen, Ph.D., R.N., Elizabeth Schlenk, Ph.D., R.N., Susan Sereika, Ph.D., Willa Doswell, Ph.D., R.N.

Introduction

Over the past decade an examination of outcomes related to patient health and well-being or quality of life has become a priority in research and clinical practice. To date the majority of the work in this area has addressed geographically or clinically homogeneous populations. Relatively little attention has been paid to the study of common quality of life outcomes across diverse populations of patients. Yet the ability to interpret outcome data within a clinical condition may be influenced by how those outcomes vary or fail to vary across clinical conditions. The opportunity to examine specific outcomes across clinical conditions, to learn more about those outcomes themselves, is limited in most single investigator studies. The Center for Research in Chronic Disorders at the University of Pittsburgh, with funding from the National Institute of Health (NIH), is attempting to address this limitation with a particular interest in three areas, i.e., quality of life, cognitive function and patient adherence to treatment regimen.

The Concept of a Research Center

Much of the value of a research center is that it provides supplemental services to ongoing research, i.e., research that permits more in-depth examination of specific focal areas. To do so, research centers may have core support groups to provide support in specific functional activities, e.g., statistical analysis, laboratory services and recruitment support. The Center for Research in Chronic Disorders (CRCD) at the University of Pittsburgh group took the concept of the research center one step further. CRCD requested that ongoing investigations related to a variety of clinical conditions add the measurement of quality of life (using the MOS SF-36) to their existing study protocols. In essence, CRCD developed additional support related to the measurement of quality of life. In addition to the SF-36, investigators in the CRCD are encouraged to measure cognitive function and adherence to treatment protocol when appropriate, although, to date, the measures used to measure these concepts vary with the nature of the cognitive condition and/or the nature of the treatment regimen. The advantage of this approach is that it permits the pooling of data across studies and populations. As a result of the statistical and data support provided through the research center, pooled analyses are conducted expanding the scientific contribution of the studies beyond their original designs.

The Design of the Center

The CRCD is organized around three core support services including: (1) administrative services that provide administrative leadership and manage pilot and feasibility programs; (2) data and statistical support services that provide design and consultation support for data management and statistical analysis and form design; and (3) information services that support internal and external scientific communication. More recently, core support services were added related to the measurement of quality of life, cognative function and compliance with treatment. Core investigators are comprised of individuals with independently funded research in chronic disorders. The specific chronic disorders have varied over time but typically have addressed AIDS, arthritic conditions, cancer, cardiovascular disease, mood disorders, pulmonary disorders, and urinary incontinence. The studies have focused on risk modification, disorder management, and/or descriptive studies. Each of the primary investigators has agreed to share data on the common variables including the quality of life data.

Data from the majority of the core studies are managed using a common software package that facilitates pooled analyses. Over time a common format for capturing sociodemographic data was developed, also to facilitate pooled analyses. This coordination was enabled by the use of consultation across a majority of projects from the data management and statistics core.

Pooled Analyses

Pooled analysis of data began in the fourth year of the project, as sufficient data were accrued in each of the studies. In the past year, three major questions have been addressed.

(1) What is the variation in quality of life across chronic disorders?1,2

(2) What is the variation in quality of life controlling across disorders when controlling for sociodemographic factors?3

(3) What is the contribution of depression to self-reported quality of life across chronic disorders?4

Further pooled analyses are planned.

None of the investigations on specific clinical conditions would have been able to address these questions. The use of common measures and common data management methods in multiple studies permits the examination of questions that can best be addressed through the use of pooled data. Such collaboration between investigators is one method to stretch the value of scientific resources and to advance our knowledge of the health and well-being of various populations.

References

1. Schlenk, E. A., Erlen, J. A., Dunbar-Jacob, J., McDowell, J., Engberg, S., Sereika, S. M., Rohay, J. M., & Bernier, M. J. (1998). Health-related quality of life in chronic disorders: A comparison across studies using the MOS SF-36. Quality of Life Research, 7, 57-65.

2. Bernier, M. J., Erlen, J. A., McDowell, B. J., & Schlenk, E. A. (1996, March). Quality of life in chronic disorders: Utility of the Medical Outcomes Study-Short Form-36 across populations. A symposium presented at the University of Texas Medical Branch at Galveston, Galveston, TX.

3. Dunbar-Jacob, J., Sereika, S., McDowell, J., & Erlen, J. A. (1996, November). Sociodemographic predictors of quality of life and functional status. A symposium presented at the Fourth National Nursing Research Conference, Nursing Care Contributions to Health Outcomes, White Sulfur Springs, WV.

4. Dunbar-Jacob, J., Erlen, J. A., Engberg, S., Dyer, J., & Schlenk, E. A. (1997, June). The relationship between depression and functional status in chronic disorders. A symposium presented at Sigma Theta Tau International Honor Society of Nursing 9th International Nursing Research Congress, Vancouver, BC, Canada