# Presentation: 829311

## Observational Study Designs for Rural Health and Health Services Research

- Ty Borders, Ph.D.
- Associate Professor
- Department of Health Policy and Management
- Department of Epidemiology
- Fay W. Boozman College of Public Health
- University of Arkansas for Medical Sciences

## Topics to Be Covered

- Major types of quantitative observational study designs
- Rationale for conducting observational studies
- Examples of observational research (specifically regarding rurality of residence and substance use)

## Quantitative Observational Study Designs

- Cross sectional (descriptive or analytical)
- Cohort (retrospective or prospective)
- Case-control

## Cohort Studies

- Onset of study

- Time

- Exposed

- Unexposed

- Eligible subjects

- Outcome

- No Outcome

-  Outcome

- No Outcome

- Direction of inquiry

## Case-Control Studies

- Onset of study

- Time

-     Controls

- Direction of Inquiry

- Cases

- Exposed

- Unexposed

- Unexposed

- Exposed

- Study Onset

## Purpose of Observational Studies

- Surveillance/Market Assessment (Descriptive)
- Describe the magnitude of health-related problems                 (e.g. epidemiological surveys to estimate prevalence)
- Identify and prioritize problems
- Determine underlying factors associated with health services accessibility, utilization, and outcomes (Analytical)
- Plan for changes to the organization and delivery of public and personal health services to improve health status
- Evaluate the effectiveness of health services

## Purpose of Observational Studies

*Complement *RCTs / experiments
- Experiments may be...
- Inappropriate (e.g. outcomes of interest, such as mortality, are often far into the future)
- Impossible (e.g. we cannot “assign” veterans to reside in a rural or urban area)
- Inadequate (e.g. results from an RCT mat not be generalizable across population subgroups, clinics, etc.)
- 	from:  Black, N. Why we need observational studies to evaluate the effectiveness of health care,* British Medical Journal *1996, 312, 1215-1218.

## Why Observational Studies?

-    “ **Most randomized trials are ‘explanatory**’   --- that is, they _provide evidence of what can be achieved in the most favourable circumstances_.”        (Black, 1996)

## Rural, Suburban, and Urban Variations in Alcohol Consumption in the U.S.: Findings from the National Epidemiologic Survey on Alcohol and Related Conditions.Borders TF, Booth BM.  Journal of Rural Health 2007;23(4):314-321.

## PURPOSE

- Describe variations in alcohol consumption across the rural, suburban, and urban areas of the U.S.
- Identify regional variations in these relationships.

## Is Suburbia Different?

- The National Center for Health Statistics’ 2001 *Rural Health Chartbook* compared mortality and chronic disease rates across very urban to very rural areas
- generally demonstrated that *suburban residents had better* physical health than persons residing in rural and urban areas
- 	(Eberhardt & Ingram, 2001)

## Urban, Suburban, and Rural

## Regional Effects

- Association between urbanicity and alcohol use could further vary by region
- Environmental, health system, and cultural factors likely differ between regions
- Some rural health scholars have argued for more regionally-focused research
- 	(Hartley, 2004; Ricketts, 2004)

## Adjusted ORs, Midwest Region

## Need for Geographically Tailored Programs

- Rather than disseminating safe drinking messages across rural areas nationally...
- Interventions would optimally target more specific places, including the rural and urban areas of the Midwest and rural Northeast.

## Longitudinal Changes in Methamphetamine and Cocaine Use in Untreated Rural Stimulant Users:  Racial Differences and the Impact of Methamphetamine Legislation

*Addiction*, In Press
- Tyrone F. Borders, Ph.D.1
- Brenda M. Booth, Ph.D.2,3
- Xiaotong Han, M.S.2
- Patricia Wright, M.P.H.2
- Carl Leukefeld, D.S.W.4
- Russel S. Falck, M.A.5
- Robert G. Carlson, Ph.D.5
- 1Dept. of Health Policy and Management, College of Public Health, UAMS, Little Rock
- 2Division of Health Services Research, Department of Psychiatry, UAMS, Little Rock
- 3HSR&D Center for Mental Healthcare Outcomes and Research,
-   Central Arkansas Veterans Healthcare System, Little Rock
- 4Department of Behavioral Science, University of Kentucky, Lexington, KY
- 5Center for Interventions, Treatment, and Addictions Research, Wright State University, Dayton, OH

## Key Questions

- Do rural stimulant users decrease use of methamphetamine (MA) or cocaine over time?
- Are there racial (African American vs. white) differences in cocaine and MA use over time?
- Do blacks/African Americans switch to MA?
- Are legally mandated restrictions of the sale of MA precursors (pseudoephedrine, ephedrine, and phenylpropanolamine) associated with MA or cocaine use?

## Parent Project: Rural Stimulant Study 

- Original Rural Stimulant Study (RSS) was conducted in rural western Ohio
- Related studies then carried out in Arkansas and Kentucky with funding NIDA
- 	(R01 DA15363 to Dr. Booth)
- Respondent-Driven Sampling
- Identified seeds through community/ethnographic work
- Seeds referred others to the study ($10/each successful referral)
- Referrals led to other referrals

## Analysis

- Baseline and 4 follow-ups
-  every 6 months for 2 years
- Analytical sample limited to persons who did NOT receive formal substance abuse treatment
- Longitudinal analyses of meth, powder cocaine, and crack cocaine use
- Generalized Estimating Equations                              (SAS Proc Genmod)

## % Using Over Time

## MA Use Over Time

|  | AOR | 95% CI |
| --- | --- | --- |
| African American 
   (ref. white)
 | 0.03* | 0.01-0.05 |
| Time | 0.61* | 0.55-0.68
 |
| Months exposed to 
meth law | 1.01 | 0.98-1.05 |

## Powder Cocaine Use Over Time

|  | AOR | 95% CI |
| --- | --- | --- |
| African American 
   (ref. white)
 | 1.20
 | 0.84-1.71  |
| Time | 0.73*
 | 0.67-0.79  |
| Months exposed to 
meth law | 1.09* | 1.05-1.13  |

## Crack Cocaine Use Over Time

|  | AOR | 95% CI |
| --- | --- | --- |
| African American 
   (ref. white)
 | 3.93*
 | 2.55-6.04  |
| Time | 0.72*
 | 0.66-0.78   |
| Months exposed to 
meth law | 1.07* | 1.04-1.10   |

## Interesting Insights

- Meth precursor laws correlated with *increased* cocaine consumption
- Diminished net public health benefit?
- Very few African Americans have initiated methamphetamine use
- Many persons stopped using stimulants *without* formal treatment

## Closing Comments Regarding Observational Studies

- Observational studies inform us of priority health and health services problems
- Observational studies are sometimes the only appropriate and feasible designs
- Observational studies complement other study designs