Removable Partial Denture

Research Methods ___________________________________________________________ Prof. Akram Al-Huwaizi

Lecture 5

Writing the Research Protocol

After proper and complete planning of the study, the plan should be written down. The protocol is the detailed plan of the study. Every research study should have a protocol, and the protocol should be written. The written protocol: • forces the investigators to clarify their thoughts and to think about all aspects of the study; • is a necessary guide if a team (not a single investigator) is working on the research; • is essential if the study involves research on human subjects or is on experimental animals, in order to get the institution’s ethical approval; • is an essential component of a research proposal submitted for funding. During the process of the development of the protocol, investigators can and should try to benefit from the advice of colleagues and experts in refining their plans. But once a protocol for the study has been developed and approved, and the study has started and progressed, it should be adhered to strictly and should not be changed. This is particularly important in multi-centre studies. Violations of the protocol can discredit the whole study. A well-thought out and well-written protocol can be judged according to three main criteria. • Is it adequate to answer the research question(s), and achieve the study objective? • Is it feasible in the particular set-up for the study? • Does it provide enough detail that can allow another investigator to do the study and arrive at comparable conclusions?

Format for the protocol
• • • The research protocol is generally written according to the following format. Project title Project abstract Project description o Introduction o Aims of the study o Methodology o Data management and analysis Ethical considerations Gender issues References

• • •

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Research Methods ___________________________________________________________ Prof. Akram

References: to articles must include author 's name, title of article, name of the journal, volume, pages and year. Use the style of the examples given below in listing the references: Book Walther DP. Walther’s Orthodontic notes. 1st ed. Wright PSG: Bristol; 1960. p. 120-31. Karam LMK. Evaluation of shear bond strength of bonded molar tubes (In vitro comparative study). Master thesis, Orthodontic Department, College of Dentistry, University of Baghdad, Iraq 2006. Thesis Journal Erickson GE, Waite DE. Mandibular asymmetry. J Am Dent Assoc 1974; article 89(2): 1369-73. 4 Research Methods ___________________________________________________________ Prof. Akram Al-Huwaizi Pilot Study It is always wise to pre-test the protocol after developing it. This is particularly important in large, new and expensive studies. What appears to be a problem-free protocol may prove to have logistic and practical problems in implementation. A pilot study is a trial to pre-test the planned research on a small sample to determine its feasibility and practicality. Weaknesses in the research process then can be corrected while the plan is still flexible. Based on the outcome of the pilot study, the protocol may be modified before the study proper is implemented. The pilot study also serves as training of the researcher and standardization of the procedures of the research work. All measurements to be performed in the main study should be included in the pilot study. Intra-examiner calibration is done by statistically comparing measurements carried twice by the researcher, with time elapse of at least two weeks between the two measurements to decrease memory bias. Inter-examiner calibration is done by statistically comparing measurements carried out by the researcher and another well- trained examiner. Types of Variables: A variable is a state, condition, concept, or event whose value is free to vary within the population. An investigator may directly manipulate a particular variable in a controlled environment (frequency of brushing or type of tooth paste used) or study a nonmanipulated variable that occurs freely in a real world setting (age or malocclusion) in which the researcher merely selects them for inclusion in a study. The types of variables include: 1- Independent or experimental variable: the variable that is directly manipulated and controlled by the investigator. It is considered to be a causal factor capable of producing a change in the dependent variable. 2- Dependent variable: it is the object of change that is observed and measured to determine the effects of the independent variable manipulation. 3- Extraneous variable: It is any event that can occur during the actual conduct of a study and could potentially cause changes in the dependent variable under observation. These events, although extraneous to the purposes of the study, are significant to the researcher because their effects could be mistaken for those of independent variable. This variable must be identified and controlled by the researcher to ensure valid research results. 5