research (case study 2)

• Research Objectives


  The culmination of all the reasoning and reading that has gone before to determine the target population, describe the research rationale and define the research variables

  
• General Types of Research Objectives


  • Descriptive
  • Measuring Instruments
  • Exploration of Relationships
  • Comparison
• Specific Aims


  Descriptive studies will usually be based on specific aims or guiding questions that describe the study's purpose
• Hypothesis


  A declarative statement that predicts the relationship between the independent and dependent variables, specifying the population that will be studied
• Purpose of the study


  To test the hypothesis and, ultimately, to provide evidence so that the researcher can accept or reject it
• Types of Hypotheses


  • Null Hypothesis (always express no difference or no relationship between the independent and dependent variables)
  • Nondirectional Hypothesis (do not predict a direction of change)
  • Directional Hypothesis (describe the relationship between variables in terms of a difference, but they also assign a direction to that difference)
• Hypothesis Complexity


  • Simple Hypothesis (includes one independent variable and one dependent variable)
  • Complex Hypothesis (contains more than one independent or dependent variable)
• Identifying a research question

  1. Selection of a research topic that sparks interest

  2. Examination of issues in clinical practice and theory

  3. Reading the professional literature

  
• Research topic


  A specific topic of interest that a researcher identifies
• Clarifying a research problem

  1. Sorting through ideas, facts and theories based on clinical experience and professional literature

  2. Determining what we know, what we don't know, and what we need to find out

  3. Narrowing down from broad clinical problems or theoretical issues to a specific question

  
• Clinical experience


  • Are new treatments more effective than established ones?
  • What outcomes can be expected following a particular intervention?
  • Would a particular treatment be more or less effective if we changed the technique of application or combined it with other treatments?
• Clinical theory


  Theories allow us to explain relationships and to predict outcomes based on given information
• Formulating a specific research question

  1. Examining the principles behind a theory

  2. Determining what clinical outcomes would support or not support the theory

  
• Professional literature


  Plays an essential role in the delineation of a research problem and deriving the specific research question
• Importance and feasibility of the research question

  • The question should be important (the "So What?" test)
  • The question should be answerable
  • The study should be feasible

  
• Target population


  The group of individuals to which the results of the study will apply
• Research rationale


  Presents a logical argument that shows how and why the question was developed, provides a theoretical framework by explaining the constructs and mechanisms behind the question, helps understand why the question makes sense
• Variables


  The building blocks of the research question, a property that can differentiate members of a group or set, can have more than one value
• Predictor variable


  An independent variable
• Outcome variable


  The dependent variable, a response or effect that is presumed to vary depending on the independent variable
• Operational definition


  Defines a variable according to its unique meaning within a study, should be sufficiently detailed that another researcher could replicate the procedure or condition
• Population


  The larger group to which research results are generalized
• Sample


  The researcher chooses a subgroup of a population
• Sampling bias


  Occurs when the individuals selected for a sample overrepresent or underrepresent certain population attributes that are related to the phenomenon under study
• Sampling bias


  Can be conscious or unconscious
• Target population


  The overall group of people to which the researcher intends to generalize findings
• Accessible population


  The portion of the target population that the researcher can access
• Inclusion criteria


  Describe the primary traits of the target and accessible populations that will qualify someone as a subject
• Exclusion criteria


  Indicate those factors that would preclude someone from being a subject
• Sampling techniques


  • Probability sampling
  • Non-probability sampling

  
• Probability sampling techniques


  • Simple random sampling
  • Systematic sampling
  • Stratified random sampling
  • Cluster sampling

  
• Non-probability sampling techniques


  • Convenience sampling
  • Quota sampling
  • Purposive sampling
  • Snowball sampling

  
• Simple random sampling


  • Is unbiased in that each selection is independent, and no one member of the population has any more chance of being chosen than any other member
  • Is drawn from the accessible population, often taken from a listing of persons, such as membership directories, or institutions, such as lists of accredited hospitals
• Systematic sampling


  • When lists are arranged alphabetically or in some other ordered fashion, an alternative approach can be used that simplifies this procedure
  • To use this sampling technique, the researcher divides the total number of elements in the accessible population by the number of elements to be selected

  
• Stratified random sampling


  • Involves identifying relevant population characteristics, and partitioning members of a population into homogeneous, nonoverlapping subsets, or strata, based on these characteristics

  
• Cluster sampling


  • Involves successive random sampling of a series of units in the population
  • The advantage of cluster sampling is its obvious convenience and efficiency when dealing with large populations

  
• Convenience sampling


  • Subjects are chosen on the basis of availability
  • Perhaps the most used and practical approach to convenience sampling is consecutive sampling, which involves recruiting all patients who meet the inclusion and exclusion criteria as they become available
• Quota sampling


  • A researcher can control for the potential confounding effect of known characteristics of a population by guiding the sampling process so that an adequate number of subjects are obtained for each stratum

  
• Purposive sampling


  • The researcher hand-picks subjects on the basis of specific criteria
  • Purposive samples are commonly used in qualitative research to assure that subjects have the appropriate knowledge and will be a good informant for the study
• Snowball sampling


  • A method that is often used to study sensitive topics, rare traits, personal networks, and social relationships