Chapter 11

Question 1

Measuring physical activity and sedentary behaviour amongst individuals and populations- subjective and objective measures

Answer 1

Subjective Measures:

1. Self-Report Questionnaires: Participants are asked to recall and report their physical activity and sedentary behavior patterns over a specific period, often using surveys or questionnaires. Examples include the International Physical Activity Questionnaire (IPAQ) and the Behavioral Risk Factor Surveillance System (BRFSS) questionnaire. Subjective measures rely on individuals’ memory and perception, making them prone to recall bias.
2. Interviews: Trained interviewers ask participants structured questions about their physical activity and sedentary behavior. Interviews allow for clarifications and follow-up questions, potentially improving the accuracy of the reported data compared to self-administered questionnaires.

Objective Measures:

1. Accelerometers: Accelerometers are wearable devices that measure acceleration and deceleration of body movement. They provide detailed information about the frequency, intensity, and duration of physical activity. Participants wear accelerometers on their body (e.g., wrist, hip) for a specified period, and the devices record movement data. Accelerometers offer real-time, objective data and are less susceptible to recall bias.
2. Pedometers: Pedometers are simple devices worn on the waist or wrist that count steps taken by the wearer. While they do not capture the intensity or type of activity, they provide a basic measure of overall physical activity levels. Pedometers are particularly useful for tracking walking-based activities.

Advantages and Disadvantages:

Advantages of Subjective Measures:
- Cost-Effectiveness: Subjective measures, such as self-report questionnaires, are often more cost-effective and easier to administer to large populations compared to objective measures.
- Contextual Information: Subjective measures can provide additional context about physical activity patterns, such as the purpose (e.g., work-related, leisure) and location (e.g., home, gym) of activities.

Disadvantages of Subjective Measures:
- Recall Bias: Participants may have difficulty accurately recalling and estimating their physical activity and sedentary behavior, leading to inaccuracies in the data.
- Social Desirability Bias: Participants might over-report their physical activity levels due to social desirability bias, providing responses that they perceive as more socially acceptable.

Advantages of Objective Measures:
- Accuracy: Objective measures, like accelerometers, provide accurate and detailed information about physical activity intensity, duration, and frequency, minimizing the impact of biases.
- Continuous Monitoring: Objective measures can track physical activity and sedentary behavior continuously, offering a comprehensive overview of an individual’s activity patterns throughout the day.

Disadvantages of Objective Measures:
- Cost and Logistics: Objective measures can be expensive to purchase, maintain, and process the data. Additionally, participant burden and compliance may be challenges in long-term studies requiring continuous monitoring.
- Limited Contextual Information: While objective measures provide precise data on movement, they often lack contextual information about the type and purpose of activities, which can be essential for a comprehensive understanding of behavior.

Question 2

2 Advantages and 2 disadvantages of:
self-report

Answer 2

Advantages of Self-Report Measures:

1. Access to Inner Experiences: Self-report measures provide researchers and clinicians access to individuals’ inner experiences, thoughts, and feelings that may not be observable by others. This information can be valuable in understanding emotions, attitudes, and perceptions, which are often difficult to assess through other methods.
2. Cost-Effectiveness and Efficiency: Self-report measures are relatively cost-effective and efficient compared to other data collection methods, such as interviews or observational studies. They can be administered to a large number of participants simultaneously, making it practical for gathering data from large samples within a shorter period, thereby saving time and resources.

Disadvantages of Self-Report Measures:

1. Social Desirability Bias: One major disadvantage of self-report measures is the potential for social desirability bias, where respondents may provide answers that they believe are socially acceptable or desirable, rather than accurate or truthful responses. This bias can lead to distorted or unreliable data, particularly when sensitive topics are being explored.
2. Limited Insight into Unconscious Processes: Self-report measures rely on individuals’ conscious awareness and willingness to disclose information. They are not well-suited for capturing unconscious thoughts, biases, or behaviors, which can be a limitation, especially in psychological research where unconscious processes play a significant role. Researchers might miss valuable insights when relying solely on self-reported data.

Question 3

2 Advantages and 2 disadvantages of:
Recall

Question 4

2 Advantages and 2 disadvantages of:
Direct observation

Question 5

2 Advantages and 2 disadvantages of:
pedometers

Question 6

2 Advantages and 2 disadvantages of:
accelerometers