Beth is looking at the treatment of people with phobias. She is investigating whether there is a relationship between how long they have been in therapy and the severity of their symptoms.

Mark scheme

Marking points from the official mark scheme (May/June 2018). The mark or mark type is shown in brackets.

1. [10] Identification of variable 1 (length of time in therapy).
2. [10] Identification of variable 2 (severity of symptoms).
3. [10] Description of ways to measure variables (e.g., questionnaires, tests, observations, clinical interviews, medical records for quantification).
4. [10] Description of sampling technique (e.g., opportunity, volunteer) and recruitment of phobic participants.
5. [10] Description of data analysis (e.g., plotting on a scattergram, calculating a correlation coefficient like Spearman's Rho).
6. [10] Mention of ethical issues (e.g., informed consent, confidentiality, right to withdraw).
7. [10] The procedure should be described in sufficient detail to be replicable, demonstrating accurate and comprehensive use of psychological terminology.
8. [4] **Weakness:** Cannot determine causality. **Explanation:** Even if a strong correlation is found, it does not mean one variable causes the other (e.g., therapy causes symptom reduction). Other factors could be influencing both. **Solution:** Conduct a longitudinal experiment with random allocation to therapy/control groups to allow for causal inferences.
9. [4] **Weakness:** Subjectivity in operationalising/measuring symptom severity. **Explanation:** Self-reports can suffer from social desirability bias, and therapist ratings can have inter-rater reliability issues. **Solution:** Use multiple objective measures (e.g., behavioural observations, physiological data) and ensure strict standardisation/training for raters.
10. [4] **Weakness:** Generalisability. **Explanation:** If participants are sourced only from one clinic, they might not represent all phobic individuals. **Solution:** Recruit a larger, more diverse sample from multiple clinics or different regions.