Design, methodological issues and participation in a multiple sclerosis case-control study
Acta Neurologica Scandinavica,  Clinical Article

Williamson DM et al. – Epidemiological studies play a key role in identifying genetic and environmental factors that are associated with complex diseases like multiple sclerosis (MS). Methodological issues arise in every study, and investigators need to be able to detect, respond to and correct problems in a timely and scientifically valid manner.

Methods
  • Individuals with definite MS were identified from a prevalence study conducted in three geographic areas.
  • The target number of cases was not reached, so an additional study area was added.
  • Identifying clinic controls was inefficient, so controls were recruited using random digit dialing.

Results
  • In total, 276 cases and 590 controls participated, but participation rates were low, ranging from 28.4% to 38.9%.
  • Only one-third (33.6%) of individuals identified in the prevalence study agreed to participate in the case–control study.
  • Cases were more likely to be non-Hispanic white and older than their source populations as identified in the preceding prevalence study (P < 0.05).
  • Most participants provided a blood sample for genotyping (91%; n = 789).

Please login or register to follow this author.
► Click here to access PubMed, Publisher and related articles...
<< Previous Article | Next Article >>

Your Unread Messages in Internal Medicine

See All >> Messages include industry-sponsored communications and special communications from MDLinx

Most Popular Internal Medicine Articles

1 Effects of tea intake on blood pressure: A meta-analysis of 21 randomized controlled trials JACC - Journal of the American College of Cardiology, October 22, 2014    Clinical Article

2 Cost-effectiveness of CT screening in the national lung screening trial New England Journal of Medicine, November 7, 2014    Evidence Based Medicine    Clinical Article
Exclusive Author Commentary

3 Effects of hyperbaric oxygen on symptoms and quality of life among service members with persistent postconcussion symptoms: a randomized clinical trial JAMA Internal Medicine, November 21, 2014    Evidence Based Medicine    Clinical Article

4 Sweetened carbonated beverage consumption and cancer risk: Meta-analysis and review European Journal of Cancer Prevention, August 1, 2014    Evidence Based Medicine    Review Article

5 The burden of disease in older people and implications for health policy and practice The Lancet, November 12, 2014    Evidence Based Medicine    Clinical Article

6 How World War 1 changed global attitudes to war and infectious diseases The Lancet, November 10, 2014    Evidence Based Medicine    Clinical Article

7 The causal effect of vitamin D binding protein (DBP) levels on calcemic and cardiometabolic diseases: a Mendelian randomization study Full Text PLoS Medicine, November 4, 2014    Free full text    Evidence Based Medicine    Clinical Article

8 Efficacy of a tetravalent dengue vaccine in children in Latin America New England Journal of Medicine, November 6, 2014    Evidence Based Medicine    Clinical Article

9 Sodium zirconium cyclosilicate in hyperkalemia New England Journal of Medicine, November 26, 2014    Evidence Based Medicine    Clinical Article

10 Changes in patients' experiences in medicare accountable care organizations New England Journal of Medicine, November 3, 2014    Evidence Based Medicine    Clinical Article

11 Milk intake and risk of mortality and fractures in women and men: cohort studies BMJ, November 11, 2014    Evidence Based Medicine    Clinical Article

12 Acupuncture for chronic knee pain: a randomized clinical trial JAMA, October 1, 2014    Evidence Based Medicine    Clinical Article

13 Nonobstructive coronary artery disease and risk of myocardial infarction JAMA, November 6, 2014    Evidence Based Medicine    Clinical Article

14 Evaluation and treatment of older patients with hypercholesterolemia: A clinical review JAMA, October 20, 2014    Clinical Article

15 Effects of vaccination on invasive pneumococcal disease in South Africa New England Journal of Medicine, November 19, 2014    Evidence Based Medicine    Clinical Article

16 Three-year denosumab treatment in postmenopausal Japanese women and men with osteoporosis: Results from a 1-year open-label extension of the Denosumab Fracture Intervention Randomized Placebo Controlled Trial (DIRECT) Osteoporosis International, November 25, 2014    Evidence Based Medicine    Clinical Article

17 An interferon-free antiviral regimen for HCV after liver transplantation New England Journal of Medicine, November 13, 2014    Evidence Based Medicine    Clinical Article

18 Aspirin in type 2 diabetes, a randomised controlled study: effect of different doses on inflammation, oxidative stress, insulin resistance and endothelial function International Journal of Clinical Practice, December 27, 2013    Clinical Article

19 Non-psychotic mental disorders in the perinatal period The Lancet, November 20, 2014    Evidence Based Medicine    Clinical Article

20 Oral contraceptive use and mortality after 36 years of follow-up in the Nurses' Health Study: prospective cohort study BMJ, November 7, 2014    Evidence Based Medicine    Clinical Article

Indexed Journals in Internal Medicine: New England Journal of Medicine, The Lancet, Archives of Internal Medicinemore