Week 2 - Frameworks, literature, & quantitative research designs

Apart of Introduction to Evidence Based Practice and Research in Health Sciences at UniSA

What is the difference between a background and foreground question?

Background question is seeking for general/basic knowledge about a condition whereas foreground question is seeking for specific knowledge to inform clinical decisions of action.

What are four frameworks to form foreground questions?

• PICO

• PECOT

• PICo

• PCC

PICO framework

A type of foreground question format where P stands for patient/population, I for intervention, C for comparison intervention, and O for outcomes.

PECOT framework

A type of foreground question format where P stands for patient/population, E for exposure (intervention), C for comparison intervention), O for outcome, and T for timeframe.

PICo framework

A type of foreground question format where P stands for patient/problem, I for interest, and C for context.

PCC framework

A type of foreground question format where P stands for patient/problem, C for concept, and C for context.

Search strategy

A systematic approach to finding relevant and accurate information by organising key terms and concepts to retrieve accurate results from databases or search engines.

How to use search strategy to search for literature (4 points)?

• Break down foreground question into concepts or key words (e.g. chocolate, mood, adults)

• Incorporate Boolean operation and truncation symbols to diversity search results (e.g. such as, or, and chocolate*)

• Add limits to retrieve fewer but relevant results to find a balance between sensitive and specific search like humans/population, language, year of publication, and type of publication is recommended.

• Refer to database list provided by institution.

What is the difference between academic and grey literature?

Academic is research that is published in peer-reviewed journals, which are typically commercially comes from other sources like government, business, industries etc…

Descriptive studies and examples

A type of research design which is often used at the start of a research process to describe trends and generating hypothesis about a novel phenomenon. Examples of descriptive studies include case report, case series, and surveys.

Observational studies

A type of research design where data is collected from observations of participants, which is ideal to describe the size of a disease problem and the characteristics of people with a particular problem.

What are the three types of observational studies?

• Cross-sectional

• Case-control

• Cohort studies

Cross-sectional study

A type of observational study design that involves looking at data from a population at one specific time. (e.g. studying the effect of alcohol and falls by sending questionnaires to all students asking about alcohol consumption and if they had a fall).

What are strengths and weaknesses of cross-sectional study?

• Strengths = Fast, inexpensive, no loss to follow up, association can be studied, and helpful to determine prevalence.

• Weaknesses = Cannot determine causality, cannot study rare outcomes, and susceptible to methodological issues.

Case-control study

A type of observational study design that involves comparing two groups, one possessing a condition of interest to a very similar group lacking that condition, used to determine the strength of the association between each predictor variable and the presence or absence of condition. (e.g. case group are students who report having falls due to regular alcohol consumption and control group are students who report not to having falls)

What are the strengths and weaknesses of the case-control study?

• Strengths = Rare outcome/long latent period, inexpensive and efficient, not prone to loss to follow up, and establishes association between exposure and outcome.

• Weaknesses = Causality still difficult to establish and is susceptible to methodological issues (like recall and forgetting information from the study).

Cohort studies

A type of observational study design that involves observing a group of participants (cohort) over a period of time, examining how certain factors affect their health outcomes. (e.g. surveying class of 2025 regarding alcohol consumption and variety of other potential covariate multiple times a year or annually over five years)

What are the strengths and weaknesses of cohort studies?

• Strengths = Know that predicator variable was present before outcome variable occurred and directly measure incidence of a disease outcome.

• Weaknesses = Expensive and inefficient for studying rare outcomes, often need long follow-up period or a very large population, and loss to follow-up affect validity of findings.

Experimental studies

A type of research design that involves manipulating one or more independent variables to observe their effect on one or more dependent variables.

What are the three types of experimental studies?

• Pre-post study

• Quasi-experimental study

• Controlled (clinical trial)

Pre-post study

A type of experimental study design used to evaluate the effectiveness of treatments by comparing results measured before and after an intervention. (e.g. steroid injection to reduce knee pain)

Quasi-experimental study

A type of experimental study design used to establish a cause-and-effect relationship between an independent and dependent variable without random assignment instead, assigning groups based on non-random criteria. (e.g. studying symptom progression between new therapy vs standard course of treatment)

Controlled (clinical) trial

A type of experimental study design which includes one study group that is compared with a control group, where the control group can receive placebo or another effective treatment.

What are the strengths and weaknesses of the controlled (clinical) trail study?

• Strengths = Simultaneous intervention is difficult due to logistical, financial, and practical reasons, investigate the effect of time of intervention on effectiveness, and investigate the effect of length of intervention on effectiveness.

• Weaknesses = Requires extensive data collection processes, very expensive, time consuming, and data analysis can be challenging.

What is the difference between randomised controlled trail (RCT), cluster RCT, and stepped wedged design?

Although all are forms of a controlled (clinical) trial; RCT is random control, cluster RCT is where participants are randomly allocated to the treatment and control group for larger scale trials, and stepped wedge design where one cluster/individual receives the intervention in each time period and data is collected each time