Trained personnel or those individuals having significant prior experience with these different instruments, and the techniques used for height assessment across varying age groups, should be hired as measurements taken by a layman may be inaccurate. Trained and experienced nursing professionals and physical anthropologists possess the required skills.

Methods for height assessment across different age groups/technique:

Methods for height assessment may be broadly grouped into two classes based on the sample of the study, i.e. living or dead. Methods used on the living may further be classified based on the age group for which it is applicable. The broad classification is:

• Height assessment in the living
• Height assessment methods in infants (up to 2 years)
• Height assessment methods in children
• Height assessment methods in adults and the elderly
• Height assessment in the dead

Height assessment methods in infants:

Height measurement in infants poses a problem, given their small size, limited control over their body, and the inability to follow instructions. In infants, the attribute of height goes more commonly by the term “recumbent length” or “crown-heel length.”  The recumbent length of an infant is measured using a simple horizontal length scale (HLS), tape measure, anthropometric rod, and an Infantometer. To measure the length of the infant clothes, diapers, hair ornaments, and objects of similar nature require removal. The head gets placed against the headboard in the Frankfurt vertical plane with the body in the supine position.  The infant is then positioned along the center of the device with the footboard against the soles of the feet. The length is noted to the nearest millimeter.[2]

 Surrogate measures to full-length measurement in infants offer certain advantages over the conventional methods. They permit estimation of length through formulae and often are more accurate than the full-length measures. Additionally, they offer an insight into the differential growth of body segments as a function of age, sex, ethnicity, and pathological conditions. Alternative measures researched include arm span and ulnar length.[3]

Height assessment methods in children:

Height is measured in children (aged 3 or more) through the use of a stadiometer or an anthropometer rod. The stadiometer is mounted on the wall for this purpose, and the child is asked to remove any footwear and/or head ornaments before noting the measurement. With the buttocks, the shoulder blades, and the back of the head against the board, the head is oriented in the Frankfurt horizontal plane (FH plane), and the headpiece gets firmly placed on the head. The reading is noted to the nearest tenth of a centimeter. An alternative to standing height measures in children is the sitting height, measured from the vertex (topmost point of the head) to the sitting surface after orienting the head in the Frankfurt horizontal plane.[4] The stadiometer is placed on a stool at a sufficient height to allow the participant’s legs to form a 90 angle with the ground.  Bone age in children is also useful as an indicator of height (as given by Bayley and Pineau table).

Height assessment methods in adults and the elderly:

The most common method used for measuring height in the case of adults and the elderly is through the use of a stadiometer or an anthropometer.  Regression equations for arm span, lower leg, foot length, shoeprint length, and recumbent length may also be used in the case of the elderly as reliable indicators of stature when standing height cannot be measured.  Radiological methods such as X-ray and CT of long bones have also been used to estimate stature.[5]

Height assessment in case of recently dead:

Stature estimation in the case of the dead becomes of prime importance from a forensic point of view. The methods used for measurement depend upon the state of decomposition of the body. In the case of the recently dead, a measuring tape is an option. A source of error here is the loss of muscle tone, causing an increase in body length and a loss of tension in the intervertebral discs once decomposition sets in which tends to reduce the total height. 

Height assessment from skeletal remains:

1. Stature estimation from complete skeletal remains - Dwight (1894) piloted the method for stature estimation from complete skeletal remains. The use of the complete skeleton involves summing up measurements of all the skeletal elements followed by the addition of a correlation factor for soft skin and muscles. Fully (1956), individually measured the skull, the vertebral column from C2-S5, the femur and tibial length and height of the calcaneus and talus. He then summed up these measurements to obtain skeletal height. Adding a soft tissue correction factor can help estimate the living stature of the same individual. 
2. Stature estimation from long bones and fragmentary skeletal remains- The former method requires the presence of the entire skeleton, which is not available in its entirety many times. In such situations, fragmentary skeletal remains are used. Research has shown cephalometric measurements to correlate with stature in the case of males and a correlation of craniometric measurements with stature in the case of both males and females.[6][7] Additionally, the bones of the body, including the sternum, sacrum, phalanges, calcaneum, and the long bones, may be used to estimate the stature of the remains.[8][9][10][9][8] Early research on deriving regression equations using long bones was carried out by Karl Pearson (1899), Pan (1924), Nat (1931), and Trotter- Gleser (1958) while research on using fragments of long bones was done by Steele and Mckern (1969). Tibia and femur have proved to be the best indicators of stature in individuals after taking into account the error margin. The length of these individual bones may be measured using an osteometric board. One end of the bone to be measured is placed at the fixed end of the board, and the other end is held in place using a crosspiece. The reading on the corresponding scale gives the physiological length of the bone.

Diurnal variations in height can be a source of error. Stature varies at different times of the day by up to 2 centimeters, with a reduction seen in the afternoons and evenings as a result of reduced elasticity of the intervertebral discs and vertebral muscles.[11] This, along with the gradual reduction in height due to senile degeneration needs to be taken into consideration when using stature as an identification parameter or for clinical diagnosis.[12]

Clinical Significance

Clinically, height is necessary for maintaining physical growth records. This is especially significant when it comes to monitoring the growth patterns of infants and children. Height assessment and the growth patterns linked to it, either directly or indirectly, point towards the socioeconomic status of an individual, amongst other things. Growth indicators such as the height of the individual and hence the BMI (Body Mass Index) can help diagnose conditions such as Marasmus and Kwashiorkor in children.[1] In the case of adolescents, height assessment constitutes a part of the selection criteria for certain sports activities. A cut off height is established as the basis for selection into sports where height confers a certain leverage. Accurate height assessment becomes crucial in these cases. Professions such as firefighters, military personnel, and lifeguards, among others, benefit from more height. Entry requirements for the same include a physical fitness test, which constitutes an assessment of height as well.

Anthropological Significance

The significance of measuring the height of individuals for an anthropological setting comes into play while studying the physical growth patterns and secular trends across regions and population groups[13]. We cannot apply established data for a particular population onto other populations and hope to expect accurate results. This can have clinical contraindications.

Forensic Significance

In forensics, stature is one of the four parameters used to identify an individual. The stature of an individual is used to identify the dead and sometimes link the individual to a scene of a crime by the process of elimination of suspects based on their height. 

Enhancing Healthcare Team Outcomes

Even though the general presumption is that height assessment is a part of the preliminary examination/ routine check-ups carried out at hospitals and health care centers, it has many underlying indications. As previously described, it can indicate several abnormalities in individuals and can be used to diagnose these conditions. However, to arrive at a correct diagnosis or accurate identification in the case of the dead and skeletal remains, a number of individuals need to partake in the activity. 

Diagnosis of clinically significant conditions require trained nursing staff to aid in the process of measuring height, and its correct interpretation requires the involvement of clinicians. Often, better outcomes takep place by involving an anthropologist. Anthropologists can help shed light on varying growth patterns across regions and use this information to indicate abnormalities, if any. 

Even though the general presumption is that height assessment is a part of the preliminary examination/ routine check-ups carried out at hospitals and health care centers, it has many other underlying indications too. As previously described, it can indicate several abnormalities in individuals and can be used to diagnose these conditions. However, to arrive at a correct diagnosis or accurate identification parameters in the case of the dead and skeletal remains, several individuals need to partake in the activity. 

Diagnosis of clinically significant conditions require trained nursing staff to aid in the process of measuring height, and its correct interpretation requires the involvement of clinicians. Better outcomes are possible by involving an anthropologist. Anthropologists, based on the accurate assessment of height, can help shed light on varying growth patterns across regions and populations and use this information to indicate abnormalities, if any.