LIMITATIONS OF THE STUDY

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1 CHAPTER 13 LIMITATIONS OF THE STUDY One of the most important responsibilities of researchers is to report on the limitations and problems in their study. When you know of problems and limitations before you are starting a study, you should discuss them in the operations research proposal. (You should report these and any additional problems that occur during the research in the write-up of the study.) Never try to conceal or misrepresent limitations and problems. Design and Analysis Limitations There is no such thing as a perfect study. Every research study has some problems with the reliability and validity of the data, the size of the sample, the questionnaire design, the implementation, or the analysis plan. Good research attempts to keep these problems to a minimum, but some problems will always remain. Remember that the researcher can commit sins of both commission and omission. In a research study proposal, it is best to recognize the limitations of your design rather than try to pretend that these limitations do not exist. For example, if you have purposively selected a study sample, do not try to pretend that this sample is representative of a much larger group. If you are forced, because of limited time and funds, to use data that may be of questionable quality (such as clinic records or service statistics), do not try to pretend that the data are completely reliable and valid. If your comparison and control groups are not equivalent, do not try to pretend that they are. Point out to the reader the problems in your study design and discuss the reasons that you think the study should be conducted despite the inevitable problems.

2 Special Situational Factors In your proposal, mention any special situations that might influence the study. In Asia and other areas of the world, for example, it is often difficult to conduct field studies during the rainy season. If this is a problem, say that the study can be conducted only in months when heavy rain does not occur. If doing your study depends on prior approval from senior government officials (which often can cause long delays), mention this fact in the proposal. 118 DESIGNING HIV/AIDS INTERVENTION STUDIES

3 What To Do: Limitations of the Study Be frank about the limitations of your study and the possible situational factors that might influence the results of the study. Mention these limitations both in the proposal and in the final report. LIMITATIONS OF THE STUDY 119

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5 CHAPTER 14 RESOURCES AND FACILITIES Available Resources and Facilities Available Most reviewers of study proposals will want to know what resources and facilities will be available for conducting the research. For example, are experienced interviewers and coders available? Is appropriate software available? Will other institutions or organizations contribute to the funding of the study? What are the qualifications of the principal investigator and how much of his or her time will be devoted to the study for example, 100 percent, 50 percent, or 10 percent? These and similar questions about the availability of resources and facilities should be addressed in the proposal. It is customary for the budget to be included in the final section of a proposal before the appendices.

6 Study Budget The budget for the research study should be realistic and should be confined to those items really necessary to conduct the study. In general, most research donors will not provide money for expensive equipment, building construction, or vehicles. Moreover, donors probably will not provide salary payments to research staff that are above what they have received on other jobs. Any local contributions or large and unusual items in the budget should be explained and justified. Be very clear about each cost item in the budget. Show the components of the item. For example, if you plan to employ interviewers, you might show their salary costs as follows: Interviewers (20 persons at Rs 500 per day x 20 days) = Rs 200,000 Arrange the budget under major cost categories (see Figure 14.1). If your study extends beyond a year, show first-year costs separately from second-year costs. Finally, if the research is to be supported by international donor funding, you may be required to itemize costs in both local currency and the currency of the donor. 122 DESIGNING HIV/AIDS INTERVENTION STUDIES

7 What To Do: Resources and Facilities 1. Describe the resources and facilities available for the study. Be sure to indicate: Whether other institutions or organizations will contribute resources. The availability of computers, trained interviewers and coders, secretarial help, vehicles, office space, and so on that will be needed to implement the research. 2. For the study budget, arrange the cost items under headings. Major headings should include the following: Salaries and benefits. Materials, supplies, and equipment. Travel and per-diem. Report publication and dissemination. 3. At the end of the budget, explain and justify any large or unusual cost items. RESOURCES AND FACILITIES 123

8 FIGURE 14.1 Example of a study budget to be submitted to an international donor for a project in Thailand ITEMIZED RESEARCH BUDGET Thai baht (B) US dollars ($) A. Salaries and benefits 1. Principal investigator, 1 (50% time), B15,000/mo. x 12 mos. 180,000 4, Associate investigator, 1 (100% time) B20,000/mo. x 12 mos. 240,000 5, Field interviewers, x 10 days 120,000 2, Secretarial services, 1 (25% time) B8,000/mo. x 12 mos. 96,000 2,182 B. Travel and per-diem Exchange rate: Baht 44 = US$1.00 (11/10/01) Subtotal 636,000 14, Air-fare, 6 round trips Bangkok-Chiang B5000 ea. 30, Local transportation (bus), Chiang Mai 20 x 10 days 20, Per-diem (investigators) Chiang Mai B400 x 18 person days 7, C. Materials and Supplies Subtotal 57,200 1, Questionnaire printing, B15 ea. 15, Pencils, computer paper, diskettes 4, Printing of final report 200 ea. 20, Subtotal 39, D. Dissemination seminar 12, Total Cost 744,200 16, DESIGNING HIV/AIDS INTERVENTION STUDIES

9 An Example of a Budget Justification LOCAL CONTRIBUTIONS The Thailand Ministry of Health will provide office space, equipment (including computers and software), communications, and utilities for the duration of the project. Study data will be entered into the computer and cleaned by Ministry data entry staff at no cost to the project. SALARIES AND BENEFITS The principal investigator is a full-time member of the operations research faculty of The Royal University. She will be employed half-time by the project at her regular university salary level rate. The money will be paid directly to the university to cover the costs of replacement faculty who will assume her teaching duties for one year. The principal investigator s salary will also continue to be paid by the university. Similarly, the secretary is an employee of the operations research department of the university. She will be released to work on this study under the same conditions as the principal investigator (see Resources and Facilities Manual, which includes the relevant personnel policies of The Royal University and a copy of the principal investigator s and the secretary s 2000 tax returns, attesting to their salary levels). The associate investigator has recently earned his doctorate in public health from Mahidol University. This is his first job and he will be paid at the rate of a new faculty member at The Royal University (see Resources and Facilities Manual, which contains the Mahidol faculty salary schedule). Field interviewers will be paid at the daily rate authorized by the Ministry of Health. Thirteen of these days will be used to supervise field interviewing and field editing and one day will be used to attend the final seminar. Per-diem rates are those authorized by the Ministry of Health for Chiang Mai. MATERIALS AND SUPPLIES Costs of printing are based on three independent bids. DISSEMINATION SEMINAR The costs of the final seminar include rental of a meeting room at the Chiang Mai Imperial Hotel and a tea break for 100 persons. TRAVEL AND PER-DIEM The principal investigator will spend three days in Chiang Mai preparing field work with local health authorities. She will also visit Chiang Mai for one day to attend the final project seminar. The associate researcher will spend 14 days in Chiang Mai. RESOURCES AND FACILITIES 125

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