"Blood pressure (BP) is the pressure exerted by circulating blood upon the walls of blood vessels and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation, usually measured at a person's upper arm. A person’s blood pressure is usually expressed in terms of the systolic (maximum) pressure over diastolic (minimum) pressure and is measured in millimeters of mercury (mm Hg). … Blood pressure varies depending on situation, activity, and disease states, and is regulated by the nervous and endocrine systems. … Chronic hypertension is a risk factor for many diseases, including kidney failure, heart attack, and stroke." – Wikipedia. Blood pressure is typically expressed in terms of the systolic pressure over diastolic pressure as if this were a single observation, yet in fact these are two separate observations taken moments apart. In some situations only one of these two are needed and recorded, and some medical devices record only one (either the diastolic or the systolic). Therefore, this abstract class defines those properties that are common to individual systolic and diastolic observations as well as the classic “blood pressure” observation that contains both systolic and diastolic values as if it were one observation. This class defines the bodySite and method that may be needed in order to interpret the observation, as well as pointers to the four qualifier observations that may affect the interpretation.

"Blood pressure (BP) is the pressure exerted by circulating blood upon the walls of blood vessels and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation, usually measured at a person's upper arm. A person’s blood pressure is usually expressed in terms of the systolic (maximum) pressure over diastolic (minimum) pressure and is measured in millimeters of mercury (mm Hg). … Blood pressure varies depending on situation, activity, and disease states, and is regulated by the nervous and endocrine systems. … Chronic hypertension is a risk factor for many diseases, including kidney failure, heart attack, and stroke." – Wikipedia. This class represents the measurement (or “clinical observation”) of the patient’s Blood Pressure. Blood pressure is typically expressed in terms of the systolic pressure over diastolic pressure as if this were a single observation, yet in fact these are two separate observations taken moments apart. Therefore, the value of this “blood pressure observation” is made up of a set of one systolic and one diastolic observation. This class also re-defines the generic clinical Observation class to fix the observed characteristic to LOINC 55284-4.

“Blood pressure (BP) is the pressure exerted by circulating blood upon the walls of blood vessels and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation, usually measured at a person's upper arm. A person’s blood pressure is usually expressed in terms of the systolic (maximum) pressure over diastolic (minimum) pressure”– Wikipedia. This class represents the measurement (or “clinical observation”) of the patient’s Diastolic Blood Pressure, which is the minimum pressure exerted by circulating blood upon the walls of blood vessels during the heart’s pumping phase. This class also re-defines the generic clinical Observation class to fix the observed characteristic to LOINC 8462-4. "Diastolic blood pressure (in mmHg)." - PCORnet Common Data Model, Vital.Diastolic

Heart rate is the speed of the heartbeat measured by the number of poundings of the heart per unit of time — typically beats per minute (bpm). The heart rate is commonly measured by observing the patient’s pulse, which is the physical expansion of the artery. The pulse commonly taken is from the radial artery at the wrist. Sometimes the pulse cannot be taken at the wrist and is taken at the elbow (brachial artery), at the neck against the carotid artery (carotid pulse), behind the knee (popliteal artery), or in the foot dorsalis pedis or posterior tibial arteries. In addition, the heart rate may be measured directly electrocardiography (adapted from Wikipedia). This class represents the measurement (or “clinical observation”) of the patient’s heart rate. This class re-defines the generic clinical Observation class to fix the observed characteristic to LOINC 8867-4 and to set the data type of the observation value to a Physical Quantity Ratio. It also redefines the bodySite and method properties such that they are bound to the Heart Rate Measurement Site and Heart Rate Measurement Method valuesets, respectively.

“Human height or stature is the distance from the bottom of the feet to the top of the head, standing erect. … Growth has long been recognized as a measure of the health of individuals” – Wikipedia. This class represents the measurement (or “clinical observation”) of the patient’s Height. This class re-defines the generic clinical Observation class to fix the observed characteristic to LOINC 8302-2 and to set the data type of the observation value to a Physical Quantity. "Height (in inches) measured by standing.... Decimal precision is permissible." - PCORnet Common Data Model, Vital.HT

“Oxygen saturation is a term referring to the fraction of oxygen-saturated hemoglobin relative to total hemoglobin (unsaturated + saturated) in the blood. The human body requires and regulates a very precise and specific balance of oxygen in the blood. Normal blood oxygen levels in humans are considered 95-100 percent. ... Levels below 80 percent may compromise organ function, such as the brain and heart” – Wikipedia. This class represents the measurement (or “clinical observation”) of the patient’s blood oxygen saturation level. This class re-defines the generic clinical Observation class to fix the observed characteristic to LOINC 2708-6 and to set the data type of the observation value to a Physical Quantity.

“The respiratory rate (RR), also known as the respiration rate, ventilation rate, ventilatory rate, ventilation frequency (Vf), respiration frequency (Rf), pulmonary ventilation rate, or breathing frequency, is the rate (frequency) of ventilation, that is, the number of breaths (inhalation-exhalation cycles) taken within a set amount of time (typically 60 seconds)” – Wikipedia. This class represents the measurement (or “clinical observation”) of the patient’s Respiration Rate. This class re-defines the generic clinical Observation class to fix the observed characteristic to LOINC 9279-1 and to set the data type of the observation value to a Physical Quantity.

“Blood pressure (BP) is the pressure exerted by circulating blood upon the walls of blood vessels and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation, usually measured at a person's upper arm. A person’s blood pressure is usually expressed in terms of the systolic (maximum) pressure over diastolic (minimum) pressure”– Wikipedia. This class represents the measurement (or “clinical observation”) of the patient’s Systolic Blood Pressure, which is the maximum pressure exerted by circulating blood upon the walls of blood vessels during the heart’s pumping phase. This class also re-defines the generic clinical Observation class to fix the observed characteristic to LOINC 8680-6. "Systolic blood pressure (in mmHg)." - PCORnet Common Data Model, Vital.Systolic

“Temperature recording gives an indication of core body temperature which is normally tightly controlled (thermoregulation) as it affects the rate of chemical reactions. … The main reason for checking body temperature is to solicit any signs of systemic infection or inflammation in the presence of a fever (temp > 38.5 °C/101.3 °F or sustained temp > 38 °C/100.4 °F), or elevated significantly above the individual's normal temperature” – Wikipedia. This class represents the measurement (or “clinical observation”) of the patient’s Temperature. This class re-defines the generic clinical Observation class to fix the observed characteristic to LOINC 8310-5 and to set the data type of the observation value to a Physical Quantity.

This class contains a collection of clinical Observations traditionally called “Vital Signs” because they are measurements of the body’s basic functions. The absence of a pulse, respiration, or blood pressure are indications that the patient is dead, hence the term “vital” in the name. Traditionally, there are four vital signs: Heart rate or pulse; Respiration rate, Blood pressure, and Body temperature. Body height and Body weight are also often included among vital signs because these measurements are often used (in conjunction with other observations) to provide a gross indication of potential health concerns. The FHIM includes a seventh vital sign, Blood oxygen saturation, as the human body requires a specific balance of oxygen in the blood below which organ function may be compromised. Another reason why vital signs are treated separately from other observations is that historically, vital signs have been located in a particular location in a paper medical record. Individual organizations or medical specialties will often include other common clinical observation under the heading of “vital signs”, such as a Pain scale or Head circumference (for newborns). The FHIM treats these measurements as simply other kinds of clinical observations. Again, there is no difference between a vital sign observation and a non-vital sign observation, other than vital signs are a named set of observations.

Human body weight refers “to a person's mass or weight. Body weight is measured in kilograms … or pounds. Strictly speaking, body weight is the measurement of weight without items located on the person. Practically though, body weight is measured with clothes on, but without shoes or heavy accessories such as mobile phones and wallets and using manual or digital weighing scales. Excess or reduced body weight is regarded as an indicator of determining a person's health, with body volume measurement providing an extra dimension by calculating the distribution of body weight.” – Wikipedia. This class represents the measurement (or “clinical observation”) of the patient’s Weight. This class re-defines the generic clinical Observation class to fix the observed characteristic to LOINC 3141-9 and to set the data type of the observation value to a Physical Quantity. "Weight (in pounds).... Decimal precision is permissible." - PCORnet Common Data Model, Vital.WT