Data collection is the gathering of information about a patient's health status. It typically includes two categories of data – subjective and objective. Subjective data are the patient's verbal description of their health, such as pain perception. In contrast, objective data includes observations or measurements of the patient's health conducted by the nurse. Data collection should be purposeful, factual, accurate, relevant, and complete. The purpose will determine the type of assessment chosen for data collection. For example, a focused assessment is required for chest pain. Collecting factual and accurate data helps to avoid misinterpretation and prevents incorrect assessment. Additionally, the data collected should be relevant to the goal of the diagnosis or assessment. Finally, the data collected must be complete in order to provide a full picture of the health problem. The three sources of data collection are primary, secondary, and other. An alert and conscious patient with no disability can be a primary data source. Family members and caregivers may provide information as secondary data sources. Other sources may be patient health records, relevant medical literature, or interdisciplinary team records.