Research Methodology Flashcards
____________ refers to the specific procedures used to identify select process and analyze information about a topic
Research methodology
___________is an indication of how sound your data is
Validity
__________is the study of methods by which knowledge is gained
Methodology
A ___________ is a characteristic of a person or object that can take up different values
Variable
The variable used to describe the problem under study is called __________
Dependent variable
A variable that is believed to influence or cause me a problem under study is called
Independent variable
A variable that is associated with the problem and the possible cause of the problem is called_______
Confounding variable
____________ is a variable whose values are expressed in categories
Categorical variables
A variable whose values are expressed in numbers is _______
Numerical variables
___________ are variables that are related to a number of independent variables that they influence the problem directly
Background variables
__________is a detailed outline of how an investigation will take place
Research design
State six types of variables
- dependent variable : the problem under study is influenced by independent variables
- independent variable:known to influence the dependent variables but is not influenced by them
- categorical variable : is express in categories eg sex
- numerical variable :is expressed numbers eg age
- confounding variables: influence both the problem and contributing factors
- background variable : influence a number of independent variables in the background
State three factors that the nature of the study design depend on.
- the nature of the problem
- the knowledge that is already available about the problem
- the resources available for the study
Explain the two main types of study designs
1) INTERVENTIONAL
- exploratory: explores to find out more info but no solutions are made
- descriptive: simply observe and describe the nature of the subject without influencing it types include case study, cross sectional surveys
- analytical: to find out if an outcome is related to exposure can be interventional or non interventional there are three main types ie analytical retrospective and prospective
2)NON INTERVENTIONAL
Researcher manipulates the objects understudy and records the outcome and can compare two groups there are two categories ie
- experimental: two groups are compared has three characteristics ie manipulation control and randomization
Quasi experimental: one of the characteristics is missing therefore is a half experiment
__________ is the type of non interventional studies that is carried out when little is known about the topic
Exploratory studies
______________is a research design that involves observing and describing the behavior of a subject without influencing it in any way
Descriptive studies
________________ is used to describe the characteristics of a phenomenon or population being studied.
Descriptive research
An intensive study about a group of people or unit is called________________
Case study
______________ are studies aimed at determining the frequency of a particular attribute
Cross sectional surveys
______________are studies done to determine if an outcome is related to exposure
Analytical studies
State three types of analytical study design
- analytical: to measure the prevalence of health outcomes and the determinants of health can be qualitative or quantitative
- retrospective: compares two groups one which the problem exists and the other in which the problem does not exist
- prospective: compare on group exposed to a risk factors and group not exposed
State one advantage of analytical study design
Retrospective and analytical studies are inexpensive and take less time
State 6 disadvantages of analytical study design
- with analytical the study results cannot be generalized
- the results are only true to the people who were studied
- selection of appropriate control groups are a major problem
- the matching of cases and controls has to be done with care
- prospective studies take longer than analytical studies and are expensive
- identifying all cases in a study population is a big problem
What are the two categories of intervention studies
-experimental and quasi experimental
State three characteristics of classical experimental studies
- manipulation:researcher does something to one group of the study
- control : researcher introduces one or more controls to compare with the other group
- randomization :the reseaher takes care to randomly select subjects to the control groups and experimental group
In _________one characteristic of the true experiment is missing
Quasi experimental
___________is a selection of a number of study units from a defined population
Sampling
The total group of individuals from which a sample can be drawn is called______________
Target population
______________is the group of people who take part in the investigation
The sample
The extent to which we can apply our findings to the target population is called ______________
- generalizability
___________ is a list of all units that compose a study population
-the sampling frame
____________is one m member of a study population
-study unit
Explain the four main aspects to consider when sampling
- study population : the population from which you will collect your sample
- sample size: how many do we need in our sample?
_sampling methods ; the availability of the sampling frame greatly impacts the choosing of a method - representativeness : to what extent does your sample represent your study population
A ____________is a population from which you will select your sample
Study population
A ___________sample has all the important characteristics from which it is drawn
Representative
State the two classifications of sampling methods
1) Non Probability: the probability of selecting each study unit is unknown
The types are
- convenience : pick who are available
-quota: pick according to certain characteristics
- purposeful : the researcher knows the best sample
2)probability: requires methods that ensure that the samples are selected by chance
The types are
Simple randomized: lottery like
Systematic : assign numbers
Stratified : divided in groups then chosen individuals
Cluster : chosen as a group
Multistage : uSe more than one method
In __________method the probability of selecting each study unit is unknown
Non probability
Explain three types of non probability sampling methods
1) convenience sampling:the ones that happen to be available are chosen , sample is not representative of population,
2) Quota: sample is chosen according to certain characteristics , ensures samples from different categories are chosen
3) purposeful:researcher has adequate knowledge of the study population to hand pick the sample
__________is a method in which the study units that happen to be available at the time of data collection are selected
Convenience sampling
A non probability sampling method in which the researcher looks for specific characteristics in their respondents to then take a tailored sample is called ___________
Quota sampling
____________ sampling is based on the belief that the researcher has adequate knowledge of the study population to hand pick the sample
Purposeful sampling
Explain the five probability sampling methods
1) Simple randomized : used the lottery method does not ensure representation
2) Systematic :chosen at regular intervals is less time consuming and easier but also does not ensure representation
3) Stratified: divide into groups then randomly select sample only possible if population is known and is more representative
4) cluster: select groups instead of individuals can be done when groups are easily chosen
5) multistage :carried out in phases using more than one method useful when dealing with huge population
_______________ is the simplest form of probability sampling
Simple randomized sampling
___________ is when individuals are chosen at regular intervals from the sampling frame
Systematic sampling
__________ is when we divide the sampling frame into groups before selecting
Stratified sampling
The selection of study units in groups rather than individually is called_____________
Cluster sampling
A ________sampling procedure is carried out in phases usually involving more than one sampling method
Multistage sampling
A systematic error in the procedure of sampling that leads to a distortion in the results of the study is called __________
Bias
Explain five biases that can take place during sampling and the remedial action that can be taken
1) non response ; person refuses to answer questions or forgets to fill in questions data collection methods must be pretested
2) improper sampling procedures: eg studying volunteers only leading to bias in the results
3) missing cases of short duration:
4) seasonal bias: results may vary in different seasons eg malnutrition do study in all seasons
5) tarmac bias: choosing areas that are easily accessible
State the two types of sample sizes
1) desirable sample size: determined by the variation of characteristics in the study population
2) feasible sample size is one that can actually be collected considering the resources
