week 4 Flashcards
What are the types of design
Cross-sectional: one sample, one measurement, one moment in time, can compare groups measures at that one moment in time
Longitudinal: one sample, more than one measurement, more than one moment in time
Time-lagged: more than one sample, one measurement, more than one moment in time
What is cross-sectional design
participants take part at only one point in time, complete questionnaire only once
Allows the examination of relationships between two or more variables at a single point of time. allows the prevalence of a psychological variable to be established within a specific group
Cross sectional strengths and weakness
strengths: quick, easy, cheap data collection. Useful for establishing relationships, flexible: administer as many measure as you like within a survey
Weaknesses: direction of relationships can’t be assessed. possibility that relationships are due to things not measured, cohort effects: single time-point finding may not be relevant in the future, consider generational changes in social attitudes
What is longitudinal studies
same participants take part more than once
Can be used to identify predicting variables, can be used to investigate levels of intra-individual changes over time within variables, repeat the same measurements at each point
What are longitudinal cohort studies
cohort studies are longitudinal studies of group of people born at about the same time. Participants are followed through long periods of time
strengths and weaknesses of longitudinal studies
Strengths: measure the effect of time or age on variables, investigate predictions rather than simply relationships. Allows for more complex statistical analyses
Weaknesses: attrition, administration cost, huge time investments, practice and fatigue effects in data, cannot modify method halfway through, can be mitigated by being a source for cross-sectional work
time-lagged design
a combination of cross-sectional and longitudinal. Study group at one point in time, then a different group at a different point in time
What are the strengths and weakness
Strengths: resource efficient. Many variable can be collected at each point. Time changes not influenced by fatigue or practice effect
weaknesses: not possible to examine intra-individual change, time-related effect may be due to cohort effects. Care needed to ensure successive cohorts are comparable, or findings may not be valid
Types of surveys
mail surveys, personal surveys, telephone interviews, online surveys
Mail surveys
distributed and returned through the post. Often distributed to specific target population samples. Questionnaires are self-administered
mail surveys advantage, disadvantages
Advantages
low cost no interviewer bias, suitable for sensitive topics
disadvantages:
low completion rates, prone to non-response bias
errors may arise from participants misunderstanding questions
personal surveys
respondents are contacted by trained interviewers, who administer the questionnaires
advantages and disadvantages to personal survey
Advantages: can make use of computer technology CAPI, more control and flexibility over how the survey is administered
disadvantages: interviewers bias= influences responses or records them incorrectly. High cost
telephone interviews
respondents are contacted by telephone by trained interviewers who administer the questionnaires over the phone
telephone interviews advantages and disadvantages
advantages: cost-effective, time-effective and can use technology CATI
disadvantages: sampling bias, interviewer bias, low response rate
