You will conduct a cohort study of students at High Pavement College over 10 years to investigate the relationship between chocolate/chip consumption and premature greying. Students will be surveyed about consumption frequency and hair will be assessed annually for greying. Other factors like stress, genetics, and sun exposure will also be tracked through surveys to control for their potential effects. Results will be analyzed to determine if those eating chips/chocolate 5+ times/week have higher rates of premature greying compared to those who don't.

1. Medical Studies

2. You are head of a team of epidemiologists working at the QMC There have been claims in reports that teenagers aged 16 – 19 who eat chips OR chocolate at least 5 times a week are more likely to suffer from premature greying of hair (before the age of 25)

3. It is your task to design a study that will either confirm or reject the claims in the reports. You have been assigned the staff and students of High Pavement college as your subjects. You have 10 years in which to complete your study. What will you do? How will you ensure that your results are fair, reliable and valid? Work with your co – epidemiologist to design the perfect study. You need to consider the costs involved You need to submit a report to the chief medical practitioner (Jemma) by the end of the lesson

4. Your plan should include… Who are you going to study? How often? How will you measure the grey hair? How will you control or take into account other factors that may cause premature grey hair? How will you keep track of people in your study?

5. COHORT STUDIES - a group of people are followed over time to see who develops the disease. Follow over time compare exposure to risk factors and draw conclusions group with condition group without condition Follow over time compare outcomes and draw conclusions group with condition group without condition Follow over time group with condition group without condition Population exposed to risk factor Population not exposed to risk factor Population OR

6. Case Control – a group of people who have the disease are compared with a group who do not have the disease cases without condition cases with condition Take histories of exposure to risk factors, compare and draw conclusions

7. Features of a good study Should include a clearly stated hypothesis or aim A representative sample selected from the wider population that the study’s conclusions will be applied to The proportion of people who drop out should be kept to a minimum Must produce valid data – the method used to collect the results must be reliable Any variables that could affect the measurements should be controlled or taken into account Conduct a survey on lifestyles The disease diagnosis must be clearly defined to ensure that different doctors record and measure the symptoms in the same way. Use a large sample The effect of all variables that could affect the disease should be considered