04

• Screening

  • Primary objective: Detection of a disease in its early stages in order to treat it and deter its progression
  • Secondary objective: Reduce cost of disease management by avoiding costly interventions required at later stages
• Advantages of Screening


  • Many screening procedures are simple and inexpensive
  • Individuals as well as larger populations can be screened
  • Single or multiple test screening can be administered often with one sample
  • An opportunity to provide health education to those who may not otherwise receive it
• Disadvantages of Screening


  • False positives and false negatives can occur
  • Those with a false positive test result will suffer needless anxiety and unnecessary medical interventions
  • Those with false negatives will have a false assurance of health and will be shattered when the disease becomes obvious. Opportunity to receive early treatment is lost
• Selection of a Screenable Disease


  • Does its significance warrant its consideration as a community problem?
  • Can the disease be detected by screening?
  • Should screening for disease be done?
  • What are the health benefits? i.e., can it be treated?
  • What are the costs associated with it?
• Significance


  • The significance of a disease is the level of priority assigned to the disease or disorder as a public health concern – it is generally determined by incidence and prevalence and by quantity (severity) and quality of life affected by the disorder
  • Determinants of significance: Quality of life, Quantity of life, Disease-specific mortality rates, Prevalence rates, Incidence rates, Cost to treat
• Is This Disease/Disorder Screenable?

  • Diagnostic criteria should be well documented and defined
  • Do screening methods exist to detect the disease in early stages - must be safe, cost-effective, accurate
  • Reliability: Reproducibility of test results, Interobserver vs. intraobserver
  • Validity: Accuracy of the test (distinguish those with/without disease), Sensitivity, Specificity
  • Consider efficiency/efficacy of mass screening programs
  • Is there community resources? Funds, workers, follow-up, treatment sources, administrative personnel
  • Development of community health program: Lead agency, Community assessment, Program constraints
• Should Screening for the Disease/Disorder Be Done?

  • Is there any benefit to early detection?
  • Are there effective treatments available?
  • Interventions/treatment modalities need to affect disease progression to justify screening, Follow-up is critical, Need to consider safety of intervention
• Ethical Considerations


  • Request for participation implies a health benefit
  • Limitations of results: Not diagnostic; identifies those at risk or who need further evaluation
  • Controversies of screening results: Misinterpretation, False positives, false negatives, Duty to inform, Cut-off points, Borderline cases
• Economic Feasibility


  • Cost-benefit ratio: Comparison of various outcomes in monetary values
  • Cost-effectiveness: Optimal use of resources to reach desired health outcome
  • Cost-efficiency: Limited budget to achieve as much desired outcome as possible
• Selection of a Screenable Population

  • Person-dependent factors: Age, gender, race/ethnicity, income level, and lifestyle
  • Environment-dependent factors: Conditions of the workplace, home, and community
• Nurses Role


  Nurses play a role in every aspect of the screening program development process including Assessment, Data analysis, Planning, Implementation, Evaluation