Six Key Concepts in IB DP Psychology (DP IB Psychology): Revision Note

IB DP Psychology is built around six key concepts that run throughout the entire course:

• Bias

• Causality

• Change

• Measurement

• Perspective

• Responsibility

These concepts appear across all content areas, which include:

• biological approach

• cognitive approach

• sociocultural approach

These concepts also apply to all of the contexts, which include:

• Health & wellbeing

• Human development

• Human relationships

• Learning and cognition

Concepts help you to analyse, evaluate and connect psychological knowledge, rather than simply describe studies or theories

• They are also Theory of Knowledge (TOK) concepts, meaning they link psychology to wider questions about how knowledge is produced, evaluated and applied across subjects

Understanding the key concepts supports critical thinking, allowing you to make balanced judgements about psychological research and theories by considering strengths, limitations and implications

When studying any psychology topic, you should ask the following questions:

• How is psychological knowledge constructed here?

• What assumptions underlie the research or theory?

• What limitations affect the findings?

• How does this connect to other theories, approaches or contexts?

There is no single correct way to apply concepts and they often overlap, e.g.

• the same idea (e.g. reductionism) may relate to more than one concept

You do not need to use all six concepts in every response; typically 3–4 relevant concepts are sufficient

Concepts should be treated as tools for thinking, not as content to memorise

Bias refers to a limitation in objective thinking, where information is interpreted through a filter of experience, expectations or preferences

In psychology, bias can influence:

• How research is designed and conducted

• How data is interpreted

• How theories are constructed

• Everyday decision-making and judgement

Bias may be explicit or implicit, and psychologists attempt to reduce it through careful research design while recognising that complete objectivity is difficult

Researcher bias and participant bias, including demand characteristics and social desirability bias, where expectations or awareness of the study influence behaviour, data collection, or interpretation

Sampling bias and the role of sampling techniques, including how opportunity, self-selected, or restricted samples reduce representativeness and limit generalisability

Confirmation bias and publication bias, including the tendency to favour results that support existing theories and the greater likelihood of positive findings being published, which can distort the research evidence base

Gender bias and cultural bias, including ethnocentrism, where findings are based on one gender or culture and inappropriately generalised to others

Cognitive biases, including availability, anchoring, and representativeness heuristics, which influence perception, judgement, memory, and decision-making in participants, observers, and researchers

Determinism, including biological and environmental determinism, and how these perspectives may bias interpretations of behaviour by underestimating human agency and choice

Credibility and reflexivity, particularly in qualitative research, including researchers’ awareness of their own assumptions and the role of inter-rater reliability in reducing interpretive bias

Positivism and reductionism, contrasted with holistic approaches, including how epistemological positions may shape research focus, methods, and conclusions by oversimplifying complex psychological phenomena

Causality refers to establishing cause-and-effect relationships between variables

In psychology causality is difficult to establish because:

• behaviour is often influenced by multiple interacting variables

• relationships between variables may be indirect or bidirectional

• correlation does not imply causation

Psychologists attempt to establish causality using controlled research methods, although ethical and practical constraints often limit the level of control

Correlation and causation, including the distinction between statistical association and true cause-and-effect relationships

Bidirectional ambiguity, including situations where it is unclear whether variable A causes variable B, variable B causes variable A, or both influence each other

Reductionist and complex explanations, including the extent to which causal accounts oversimplify behaviour or acknowledge interactions between biological, cognitive, and sociocultural factors

Internal and external validity, including whether a study’s design allows confident causal conclusions and whether those conclusions can be generalised beyond the research setting

Control of extraneous and confounding variables, including the use of standardisation, random allocation, and controlled procedures to strengthen causal inference

Placebos, double-blind procedures, and wait-list controls, including their role in reducing expectancy effects and alternative explanations in experimental research

Statistical significance and effect size, including the distinction between meaningful causal effects and findings that are statistically significant but limited in practical importance

Agency and motivation, including how human choice, intention, and meaning complicate simple cause-and-effect explanations

Change refers to how behaviour develops, adapts or is altered over time

In psychology, change can be:

• gradual, such as development and maturation

• sudden, such as mood or behavioural changes

• planned, such as therapy, education or health interventions

• unplanned, such as illness or trauma

A key debate in psychology concerns the extent to which behaviour is shaped by free will (agency) versus determinism

Psychologists investigate how behaviour can be changed and evaluate the effectiveness of interventions at individual, community and global levels

Development and maturation, including natural changes in behaviour, cognition, or emotion over time that may occur independently of specific interventions or experiences

Biological and environmental determinism, including how genetic, neurological, or environmental factors may constrain or facilitate the extent to which change is possible

Agency and motivation, including the role of individual choice, effort, and readiness to change, and how personal motivation influences the success of behavioural or psychological change

Barriers to change and resistance to change, including habits, social pressures, structural inequalities, stigma, or lack of resources that may prevent or slow change

Prevalence of behaviours, including changes in how common certain behaviours, attitudes, or conditions are over time within a population, often linked to social or cultural change

Intervention, prevention, and health promotion strategies, including attempts to bring about change at the individual, group, or population level through education, policy, or psychological intervention

Effectiveness of treatments, including whether observed changes are meaningful, sustained over time, and superior to no treatment or alternative approaches

Use of longitudinal and repeated-measures designs, including their role in tracking change over time and distinguishing short-term effects from lasting change

Measurement refers to how psychologists observe, define and quantify behaviour

Human behaviour is often:

• difficult to observe directly

• context-dependent

• influenced by interpretation

To measure behaviour effectively, psychologists must:

• operationalise variables clearly

• choose appropriate research methods

• ensure reliability and validity

Measurement may involve a range of evidence types and often benefits from triangulation to increase credibility

Choice of research method, including how experiments, interviews, surveys, observations, or case studies influence what can be measured and the type of data produced

Constructs and variables, including the distinction between abstract psychological constructs (e.g. self-esteem, stress) and the variables used to represent them in research

Operationalisation of variables, including how constructs are translated into measurable variables through tasks, scales, or indicators, and how this affects validity

Quantitative and qualitative data, including differences in numerical measurement versus descriptive data and how each contributes to understanding psychological phenomena

Self-reported, empirical, and anecdotal data, including strengths and limitations of relying on participants’ reports compared to observed or objectively recorded data

Direct and indirect measures, including whether behaviour or psychological processes are measured directly or inferred from indicators such as test performance or physiological responses

Brain imaging techniques (e.g. MRI, fMRI), including their use in measuring brain structure or activity and the assumptions involved in linking neural data to behaviour or cognition

Statistical significance and Type I / Type II errors, including the risk of false positives or false negatives when interpreting measured effects

Longitudinal and cross-sectional designs, including how repeated measurement over time compares with single-time-point measurement in capturing change

Prospective and retrospective approaches, including differences between measuring variables as events unfold versus relying on participants’ recall of past experiences

A perspective refers to a particular way of understanding and explaining behaviour

IB DP Psychology uses three main perspectives:

• biological

• cognitive

• sociocultural

Each perspective:

• is based on different assumptions about behaviour

• uses different research methods

• offers different explanations of behaviour

No single perspective fully explains behaviour; a multi-perspective approach provides a more complete understanding

Psychological theories and models, including how different theoretical frameworks (e.g. biological, cognitive, sociocultural) shape research questions, methods, and interpretations of behaviour

Reductionism and holism, including whether behaviour is explained by breaking it down into simpler components or by considering interactions between biological, cognitive, and sociocultural factors

Emic and etic approaches, including the use of culture-specific (emic) versus cross-cultural (etic) perspectives in understanding behaviour and experience

Deductive and inductive reasoning and data analysis, including theory-driven hypothesis testing versus data-driven theory building

Alternative explanations and interpretations, including the consideration of competing accounts for findings and the extent to which conclusions are tentative or open to revision

Cultural and Indigenous perspectives, including the recognition of diverse ways of knowing, valuing, and understanding psychological phenomena, and the importance of context and cultural meaning in interpretation

Responsibility refers to the ethical and social obligations of psychologists in their research and practice

Because psychologists work with humans (and sometimes animals), ethical standards are essential to:

• protect participants

• minimise harm

• maximise benefits

Ethical considerations can influence research design, participant behaviour and the validity of findings

Psychologists are also responsible for how research is applied in society

Ethical standards in research, including adherence to professional guidelines that ensure respect, dignity, and protection for participants throughout the research process

Informed consent, including providing participants with sufficient information about the study’s purpose, procedures, and potential risks so that participation is voluntary and informed

Right to withdraw, including participants’ ability to leave the study at any time without penalty or negative consequences

Protection from harm, including minimising physical, psychological, and social risks, particularly when research involves sensitive topics or vulnerable groups

Use of deception and debriefing, including the ethical justification for deception and the responsibility to fully explain the true purpose of the study afterwards

Anonymity and confidentiality, including safeguarding participants’ identities and personal data to prevent embarrassment, distress, or social harm

Cost–benefit analysis, including weighing the potential benefits of the research against any risks or discomfort to participants

Use of animals and child participants, including additional ethical safeguards, minimising harm, and ensuring research is necessary and justified

Socially sensitive research, stigma, and advocacy, including researchers’ responsibility to avoid reinforcing stereotypes, to communicate findings carefully, and to advocate for positive social change where appropriate