Purpose
After completing Competency #4, you will be able to identify factors that affect data quality, decide what sampling data are appropriate for the PHA process, and determine what additional data are needed.

Courses and Training Videos
Modules
- Online Public Health Assessment Training (PHAT) - Complete this series of eight online and interactive modules to learn the fundamentals of the public health assessment (PHA) process. For this competency, please review PHAT Module 5.
- PHAT Module 5: Selection of Sampling Data - In this module, you will learn how to select appropriate sampling data for the PHA, assess its quality, and identify and fill data gaps.
Guidance
Online Public Health Assessment Guidance Manual (PHAGM)
Refer to ATSDR's PHAGM to learn about the methods and resources that you can use to evaluate environmental exposures associated with environmental contamination. For this competency, please review PHAGM's section 5 (Selecting Sampling Data).
- Selecting Sampling Data. In this section from PHAGM, you will find information on how to evaluate the usability and quality of environmental and biological sampling data to examine environmental contamination at a site. It has subsections covering (1) Types of Sampling Data, (2) Evaluating Sampling Data, (3) Identifying and Filling Data Gaps, (4) Evaluating Modeled Data, and (5) Considering Background Concentrations.
- Data Needs for the PHA Process - Use this reference document, from the PHAGM resource page, to learn about the site information and data that you will usually need to obtain to conduct the PHA process assessment.
Sampling Guidance
ATSDR has two guidance documents that instruct health assessors how to calculate exposure point concentrations (EPC) using discrete and non-discrete (composite) sample designs. EPCs are used to calculate site-specific doses and air concentrations.
- ATSDR's Discrete Sampling Guidance - This document provides you with ATSDR's guidance and methods for estimating EPCs using environmental data from a discrete sample design.
- ATSDR's Non-Discrete (Composite) Sampling Guidance - This document provides you with ATSDR's guidance and methods for estimating EPCs when using environmental data from non-discrete sample designs, such as composite samples or incremental sample methods.
- Exposure Unit Guidance: Refer to the Exposure Unit Guidance to learn about what exposure units are and how they are important in determining the EPC.
Tools
- Environmental Medium-Specific Issues Checklist - This table is designed to help you, as a health assessor, navigate through some basic features of reviewing sampling data. Its purpose is to serve as a reminder of those issues that you need to consider when reviewing data.
- Example Questions and Answers for Helping Determine Data Representativeness - This table provides you with questions to help you examine sampling data and determine if they are representative of site exposures.