Lesson 4Page 1 of 27 Lesson 4 Sources of Routinely Collected Data for Surveillance

Lesson 4Page 2 of 27 Objectives for Lesson 4 Describe notifiable disease and reporting mechanisms Describe vital statistics Define and describe sentinel surveillance Describe uses of surveys Describe registries

Lesson 4Page 3 of 27 Objectives for Lesson 4 (continued) Describe surveys Differentiate between surveys and registries Describe types of administrative data-collection systems

Lesson 4Page 4 of 27 Types of Surveillance Selected individuals report Passive: initiated by provider Active: initiated by the health department Sentinel

Lesson 4Page 5 of 27 Limitations of Reporting Systems Under reporting Incomplete reporting * If consistent surveillance methods are used, data will describe trends despite under reporting

Lesson 4Page 6 of 27 Factors Contributing to Incomplete Reporting Concealment due to social stigma Lack of awareness of requirements Inadequate knowledge of case definitions Changes in procedures Variations in diagnosis skills Low priority

Lesson 4Page 7 of 27 Strengths of Reporting System Quick information Detect changes in patterns Detection of outbreaks Availability of information from all jurisdictions Basis for prevention recommendations

Lesson 4Page 8 of 27 Potential Changes in Notifiable Disease Reporting Increased: Reliance on laboratory-based reporting Use of sentinel health care providers Use of sentinel sites Use of computerized data bases

Lesson 4Page 9 of 27 Vital Statistics Only health related data available in many countries in a standard format Often the only source available for estimating rates for small geographical areas

Lesson 4Page 10 of 27 Uses of Vital Statistics Identify differences in health status within groups Assess differences by geographic area or occupation Monitor deaths considered to be preventable Generate hypotheses regarding possible cause/correlates of disease Conduct health planning activities Monitor progress towards health goals

Lesson 4Page 11 of 27 Birth Certificates Responsibility of states in U.S. Adoption of standard certificates encouraged Usually filed within 24 hours Includes date, time, and additional information

Lesson 4Page 12 of 27 Death Certificate Information Cause of death Interval between onset of condition and death Other important medical conditions Manner of death Whether an autopsy was performed Whether medical examiner/coroner was notified

Lesson 4Page 13 of 27 ICD-9 A tabular list of categories and conditions including: –code numbers –definitions of key terms –rules for selecting underlying causes of death –lists of conditions for statistical summaries Useful for: –classifying conditions –calculating rates

Lesson 4Page 14 of 27 Issues in comparability and quality control Factors influencing quality of vital statistics Factors influencing comparability of vital statistics Population estimates Population undercounts Comparison of cause-specific rates Impact of use of certain ICD codes

Lesson 4Page 15 of 27 Surveillance Systems Based on Vital Statistics Weekly reports (some) Monthly or quarterly reports Infant mortality and other adverse reproductive outcomes Occupational mortality Additional sources

Lesson 4Page 16 of 27 Sentinel Surveillance Encompasses a wide range of activities focused on monitoring key health indicators in general or in special populations

Lesson 4Page 17 of 27 Sentinel refers to Key health events Clinics or other sites at which health events are monitored Reporters who report specific health events

Lesson 4Page 18 of 27 Sentinel Sites Hospitals Clinics Counties

Lesson 4Page 19 of 27 Role of Sentinel Sites Monitor conditions for which information is not otherwise available Monitor conditions in subgroups which are more vulnerable than general population

Lesson 4Page 20 of 27 Sentinel Providers Report surveillance data Higher quality data Can be used to calculate or estimate disease morbidity

Lesson 4Page 21 of 27 Uses for Registries Monitor chronic disease Link information from multiple sources over time Collect data systematically Identify opportunities for disease control and prevention

Lesson 4Page 22 of 27 Types of Registries Case series and hospital-based Population-based Exposure

Lesson 4Page 23 of 27 Surveys Provide information for assessing prevalence of health conditions and risk Monitor changes in prevalence over time Assess knowledge, attitudes, and practices

Lesson 4Page 24 of 27 Differences Between Survey and Registry Individuals usually queried only once in a survey Data obtained by interview in a survey Surveyed population is generally representative of source population

Lesson 4Page 25 of 27 Types of Surveys Health Interview Surveys NHIS, GHS, BRFSS, YRBS Provider-based Surveys NHDS, NAMCS, NDTI Other Surveys NSFG, NHANES

Lesson 4Page 26 of 27 Administrative Data Collection Systems Availability and usefulness Integrated health information systems Hospital discharge data systems Emergency room data collection Ambulatory care data

Lesson 4Page 27 of 27 Data Collection Systems Home Accident Surveillance System (HASS) European Home and Leisure Accident Surveillance System (EHLASS) National Electronic Injury Surveillance System (NEISS) Drug Abuse Warning Network (DAWN) Poison control centers, burn units, trauma registries