longitudinal


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Related to longitudinal: Longitudinal wave, longitudinal axis, Longitudinal design

lon·gi·tu·di·nal

(lon'ji-tū'di-năl), [TA]
1. Running lengthwise; in the direction of the long axis of the body or any of its parts. Synonym(s): longitudinalis [TA]
2. Studied over a period of time, diachronic; contrast with cross-sectional or synchronic, which give equivalent results only under certain strict conditions of stability and equilibrium. Such strict attention to these conditions is of the greatest importance in the study of survivorship either in demographics or in cell economy (for example, survival pattern of erythrocytes and platelets).
[L. longitudo, length]

longitudinal

[lon′jəto̅o̅′dənəl]
Etymology: L, longitudo, length
1 pertaining to a measurement in the direction of the long axis of an object, body, or organ, such as the longitudinal arch of the foot.
2 pertaining to a scientific study (nonexperimental research design) that is conducted over a long period of time, such as the Framingham (Massachusetts) Study of heart disease, with data collected from study participants at more than one point in time. Compare cross-sectional.

lon·gi·tu·di·nal

(lon'ji-tū'di-năl) [TA]
1. Running lengthwise; in the direction of the long axis of the body or any of its parts.
2. Data studied over a period of time, diachronic; contrast with cross-sectional or synchronic, which give equivalent results only under certain strict conditions of stability and equilibrium.
[L. longitudo, length]

longitudinal

(lŏn″jĭ-tood′ĭ-năl, ĭ-tū′) [L. longitudo, length]
1. Parallel to the long axis of the body or part.
2. Continuing or lasting for some time. A longitudinal study follows its subjects from month to month or year to year
References in periodicals archive ?
There is a need to go beyond lateral thinking and also do longitudinal thinking.
The capability to integrate primary market research with audited promotional data from PCPs, Specialists and Pharmacists, and merge it with longitudinal patient level data is what sets the company apart from its competition.
Other longitudinal investigations that have examined the long-term effects of interventions on developmental outcomes are found in studies by Olds (Olds et al.
The compressive strength of SYP bark, like wood, is greatest in the longitudinal direction.
Our research uniquely adds persistence to graduation as a longitudinal dependent variable.
They suggested women they knew through social networks or kinship, as well as women who were enrolled in the longitudinal study, who seemed open and forthcoming during the staff-administered study questionnaire sessions.
The longitudinal nature of this study provided a unique look at the role of different types of dissonance over a longer period of time.
In an attempt to solve this problem, the Jacobsen team cobbled together data from the federal longitudinal "Prospects" study's Cohort 1 to measure children's test scores in 1st and 2nd grades (1992-93); Prospects Cohort 3 for scores in 3rd and 5th grades (1991-93); Prospects Cohort 7 for 7th and 9th grades (1991-93); and the National Education Longitudinal Study to measure 10th- and 12th-grade scores (1990-92).
To increase areal densities in longitudinal recording, as well as increase overall storage capacity, the data bits on a disc must be made smaller and put closer together.
Figure 9 indicates the application of the feature of longitudinal mixing for making up what will be lacking in predispersion in the drop from an internal mixer operated at reduced cycle-time.
With a valid comparison group and longitudinal earnings records, it is now possible to examine employment outcomes that may be attributable to VR service provision.
The proposed American Recovery and Reinvestment Act (ARRA) Stage 2 Meaningful Use criteria require healthcare organizations to record longitudinal care plans for 20 percent of patients with high-priority health conditions.