Scientific processes

Overview

Scientific processes cover the fundamental methodologies required to conduct and report psychological research. This topic is the bedrock of the entire GCSE Psychology specification. Examiners expect candidates not just to know definitions, but to be able to apply these concepts to novel scenarios, design their own studies, and critically evaluate the research of others. Mastering this area is essential, as research methods questions appear in almost every exam paper and often carry high mark weightings.

The Research Process

Aims and Hypotheses

Date(s): Fundamental to all psychological research.

What happened: Before conducting research, psychologists must establish what they are trying to achieve and what they expect to find.

Why it matters: A clear aim and a testable hypothesis are essential for ensuring research is focused and scientific.

Specific Knowledge:

• Aim: A general statement of the researcher's intention (e.g., 'To investigate the effect of sleep on memory').
• Hypothesis: A precise, testable statement predicting the outcome of the study.
• Directional (One-tailed) Hypothesis: Predicts the specific direction of the results (e.g., 'Participants who sleep 8 hours will recall more words than those who sleep 4 hours').
• Non-directional (Two-tailed) Hypothesis: Predicts a difference will exist, but not which direction it will go (e.g., 'There will be a difference in the number of words recalled between participants who sleep 8 hours and those who sleep 4 hours').

Variables and Control

Role: The core components of any experiment.

Key Actions: Researchers manipulate the Independent Variable (IV) to observe its effect on the Dependent Variable (DV).

Impact: Proper control of variables is what allows psychologists to establish cause and effect.

Specific Knowledge:

• Operationalisation: Defining variables in a way that makes them precisely measurable (e.g., defining 'memory' as 'number of words recalled from a 20-word list').
• Extraneous Variables: Any variable other than the IV that could affect the DV if not controlled.
• Confounding Variables: Uncontrolled extraneous variables that have systematically affected the DV, meaning we cannot be sure if the IV caused the change.
• Control Techniques: Random allocation, standardisation, counterbalancing.

Sampling Methods

Role: Selecting participants for a study.

Key Actions: Researchers must choose a sample from the target population.

Impact: The sampling method determines how representative the sample is, and therefore how far the results can be generalised.

Specific Knowledge:

• Random: Every member of the target population has an equal chance of selection. Unbiased, but time-consuming.
• Systematic: Every nth person from a list is selected. Practical, but can be biased if the list has a hidden pattern.
• Stratified: The sample reflects the proportions of subgroups (strata) in the population. Highly representative, but very time-consuming.
• Opportunity: Selecting whoever is available and willing. Quick and easy, but highly biased.
• Volunteer: Participants self-select by responding to an advert. Participants are motivated, but volunteer bias occurs (they may share specific traits).

Experimental Designs

Role: Allocating participants to experimental conditions.

Specific Knowledge:

• Independent Groups: Different participants in each condition. Avoids order effects, but participant variables may confound results.
• Repeated Measures: The same participants in all conditions. Controls participant variables, but introduces order effects (practice/fatigue). Managed via counterbalancing.
• Matched Pairs: Different participants in each condition, but matched on key variables (e.g., age, IQ). Reduces participant variables without order effects, but time-consuming to match perfectly.

Ethics and the BPS Code

Role: Protecting participants and the reputation of psychology.

Specific Knowledge:

• Informed Consent: Participants must agree to take part knowing the true aims of the study.
• Deception: Misleading participants is generally avoided, but permitted if scientifically justified and followed by a full debrief.
• Protection from Harm: Participants must not face greater physical or psychological risk than in everyday life.
• Confidentiality: Personal data must be kept private (often via anonymity).
• Right to Withdraw: Participants can leave the study at any time and have their data destroyed.

Podcast Audio Lesson

Listen to our comprehensive 13-minute audio lesson covering all the core concepts of Scientific Processes, complete with exam tips and a quick-fire recall quiz.