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PubMed2003

Lung cancer rates convergence in young men and women in the United States: analysis by birth cohort and histologic type.

Age-specific rates of lung cancer have been consistently higher for men than for women in the United States, due primarily to different patterns of cigarette smoking. Gender differences in cigarette smoking have diminished in recent birth cohorts, however, especially among whites. We used U.S. population-based incidence and mortality data and examined trends in age-specific rates of lung cancer by birth cohort according to gender, ethnic group, and histology to evaluate the generational changes in U.S. lung cancer risk for men vs. women. All tests of statistical significance are 2-sided (95% confidence interval [CI]). Lung cancer mortality rates have converged between men and women born after 1960, especially in whites. The male-to-female (M:F) mortality rate ratio for ages 35-39 years decreased from 3.0 (95% CI = 2.7-3.4) around the 1915 birth cohort to 1.1 (95% CI = 1.0-1.1) around the 1960 birth cohort among whites and from 4.0 (95% CI = 3.2-5.0) around the 1925 birth cohort to 1.5 (95% CI = 1.3-1.7) around the 1960 birth cohort among blacks. Similarly, incidence rates for white men and women converged rapidly for adenocarcinoma, small cell carcinoma, and large cell carcinoma, but less so for squamous cell carcinoma. These findings reflect the smoking patterns among white and black men and women: cigarette smoking prevalence at age 24 was essentially equal among white men and women born after 1960 but continued to be higher in black men than women. The convergence of lung cancer death rates among men and women born after 1960s supports the idea that males and females maybe equally susceptible to develop lung cancer from a given amount of cigarette smoking, rather than the hypothesis that women are more susceptible.

Adenocarcinoma↗
PubMed2007

Convergence of third order correlation energy in atoms and molecules.

We have investigated the convergence of third order correlation energy within the hierarchies of correlation consistent basis sets for helium, neon, and water, and for three stationary points of hydrogen peroxide. This analysis confirms that singlet pair energies converge much slower than triplet pair energies. In addition, singlet pair energies with (aug)-cc-pVDZ and (aug)-cc-pVTZ basis sets do not follow a converging trend and energies with three basis sets larger than aug-cc-pVTZ are generally required for reliable extrapolations of third order correlation energies, making so the explicitly correlated R12 calculations preferable.

Journal Article↗
PubMed2000

Multipole approach to the inverse problem in electrocardiology: convergence of the multipole equivalent generator on the inhomogeneous body conductor.

The multipole approach to the inverse electrocardiological problem consists of estimating the multipole components of the cardiac electric generator, starting from the measured body surface potential. This paper presents a critical investigation of the basic premise for the applicability of the multipole approach, namely the convergence of the multipole equivalent generator for the heart on the surface of an inhomogeneous body conductor. As an extension to multipole theory, a criterion for the convergence is derived. Based on realistic models for the body conductor and the cardiac electric generator, we observe that the criterion is not strictly satisfied in realistic conditions. Numerical simulations with the same models point out that the multipole equivalent generator is indeed not convergent in the strict mathematical sense. On the other hand, we show that the multipole equivalent generator yields a rather close approximation of the electrocardiological potential for intermediate values of the order of the multipole generator. A discussion is given on how to explain the apparently ambiguous results for the estimation of cardiac multipole components.

Computer Simulation↗
PubMed1998

Functional interactions of genes mediating convergent extension, knypek and trilobite, during the partitioning of the eye primordium in zebrafish.

Vertebrate eye development in the anterior region of the neural plate involves a series of inductive interactions dependent on the underlying prechordal plate and signals from the midline of the neural plate, including Hedgehog. The mechanisms controlling the spatiotemporal expression pattern of hedgehog genes are currently not understood. Cyclopia is observed in trilobite (tri) and knypek (kny) mutants with affected convergent extension of the embryonic axis during gastrulation. Here, we demonstrate that tri mutants show a high frequency of partial or complete cyclopia, kny mutants exhibit cyclopia infrequently, while knym119 trim209 double-mutant embryos have dramatically reduced convergent extension and are completely cyclopic. We analyzed the relationships between the convergent extension defect, the expression of hedgehog and prechordal plate genes, and the formation of cyclopia in knym119 and trim209 mutants. Our results correlate the cyclopia phenotype with the abnormal location of hh-expressing cells with respect to the optic primordium. We show that cyclopia in these mutants is not due to an incompetence of tri and kny cells to respond to Hedgehog signaling. Rather, it is a consequence of exceeding a critical distance (>40-50 micrometer) between hedgehog-expressing cells and the prospective eye field. We hypothesize that at this distance, midline cells are not in an appropriate position to physically separate the eye field and that HH and other signals do not reach the appropriate target cells. Furthermore, tri and kny have overlapping functions in establishing proper alignment of the anterior neural plate and midline cells expressing shh and twhh genes when the partitioning of the eye primordium takes place.

Animals↗
PubMed2001

Pancreas development in zebrafish: early dispersed appearance of endocrine hormone expressing cells and their convergence to form the definitive islet.

To begin to understand pancreas development and the control of endocrine lineage formation in zebrafish, we have examined the expression pattern of several genes shown to act in vertebrate pancreatic development: pdx-1, insulin (W. M. Milewski et al., 1998, Endocrinology 139, 1440-1449), glucagon, somatostatin (F. Argenton et al., 1999, Mech. Dev. 87, 217-221), islet-1 (Korzh et al., 1993, Development 118, 417-425), nkx2.2 (Barth and Wilson, 1995, Development 121, 1755-1768), and pax6.2 (Nornes et al., 1998, Mech. Dev. 77, 185-196). To determine the spatial relationship between the exocrine and the endocrine compartments, we have cloned the zebrafish trypsin gene, a digestive enzyme expressed in differentiated pancreatic exocrine cells. We found expression of all these genes in the developing pancreas throughout organogenesis. Endocrine cells first appear in a scattered fashion in two bilateral rows close to the midline during mid-somitogenesis and converge during late-somitogenesis to form a single islet dorsal to the nascent duodenum. We have examined development of the endocrine lineage in a number of previously described zebrafish mutations. Deletion of chordamesoderm in floating head (Xnot homolog) mutants reduces islet formation to small remnants, but does not delete the pancreas, indicating that notochord is involved in proper pancreas development, but not required for differentiation of pancreatic cell fates. In the absence of knypek gene function, which is involved in convergence movements, the bilateral endocrine primordia do not merge. Presence of trunk paraxial mesoderm also appears to be instrumental for convergence since the bilateral endocrine primordia do not merge in spadetail mutants. We discuss our findings on zebrafish pancreatogenesis in the light of evolution of the pancreas in chordates.

Amino Acid Sequence↗
PubMed2002

Xenopus Cdc42 regulates convergent extension movements during gastrulation through Wnt/Ca2+ signaling pathway.

Rho GTPases are molecular switches that regulate many essential cellular processes, including actin dynamics, cell adhesion, cell-cycle progression, and transcription. We have isolated the Xenopus homolog of Rho GTPase Cdc42 and examined its potential role during gastrulation movements in early Xenopus embryos. XCdc42 is expressed in tissues undergoing extensive morphogenetic changes, such as the deep layers of involuting mesoderm and posterior neuroectoderm during gastrulation, and somitic mesoderm at neurula stages. Overexpression of either wild-type (WT) or dominant-negative (DN) XCdc42 interferes with convergent extension movements in intact embryos, activin-stimulated animal caps, and dorsal marginal zone explants. These effects occur without affecting mesodermal specification. Overexpression of WT or DN XCdc42 leads to the decrease and increase of cell adhesiveness of blastomeres, respectively, as demonstrated by the cell adhesion assay. In addition, when overexpressed, PKC-alpha, XWnt-5a, and Mfz-3 inhibit activin-induced convergent extension in animal cap explants. This inhibition can be rescued by coexpression of DN XCdc42, implying that XCdc42 acts downstream of the Wnt/Ca2+ signaling pathway involving PKC activation. XCdc42 also lies downstream of XWnt-5a in the regulation of Ca2+-dependent cell adhesion. Taken together, our results suggest that XCdc42 plays a role in the regulation of convergent extension movements during gastrulation through the protein kinase C-mediated Wnt/Ca2+ pathway.

Amino Acid Sequence↗
PubMed1992

Self-organizing maps: stationary states, metastability and convergence rate.

We investigate the effect of various types of neighborhood function on the convergence rates and the presence or absence of metastable stationary states of Kohonen's self-organizing feature map algorithm in one dimension. We demonstrate that the time necessary to form a topographic representation of the unit interval [0, 1] may vary over several orders of magnitude depending on the range and also the shape of the neighborhood function, by which the weight changes of the neurons in the neighborhood of the winning neuron are scaled. We will prove that for neighborhood functions which are convex on an interval given by the length of the Kohonen chain there exist no metastable states. For all other neighborhood functions, metastable states are present and may trap the algorithm during the learning process. For the widely-used Gaussian function there exists a threshold for the width above which metastable states cannot exist. Due to the presence or absence of metastable states, convergence time is very sensitive to slight changes in the shape of the neighborhood function. Fastest convergence is achieved using neighborhood functions which are "convex" over a large range around the winner neuron and yet have large differences in value at neighboring neurons.

Algorithms↗
PubMed1992

Spatio-temporal convergence (STC) in otolith neurons.

It has been recently demonstrated that some primary otolith afferents and most otolith-related vestibular nuclei neurons encode two spatial dimensions that can be described by two vectors in temporal and spatial quadrature. These cells are called broadly-tuned neurons. They are characterized by a non-zero tuning ratio which is defined as the ratio of the minimum over the maximum sensitivity of the neuron. Broadly-tuned neurons exhibit response gains that do not vary according to the cosine of the angle between the stimulus direction and the cell's maximum sensitivity vector and response phase values that depend on stimulus orientation. These responses were observed during stimulation with pure linear acceleration and can be explained by spatio-temporal convergence (STC) of primary otolith afferents and/or otolith hair cells. Simulations of STC of the inputs to primary otolith afferents and vestibular nuclei neurons have revealed interesting characteristics: First, in the case of two narrowly-tuned input signals, the largest tuning ratio is achieved when the input signals are of equal gain. The smaller the phase difference between the input vectors, the larger the orientation differences that are required to produce a certain tuning ratio. Orientation and temporal phase differences of 30-40 degrees create tuning ratios of approximately 0.10-0.15 in target neurons. Second, in the case of multiple input signals, the larger the number of converging inputs, the smaller the tuning ratio of the target neuron. The tuning ratio depends on the number of input units, as long as there are not more than about 10. For more than 10-20 input vectors, the tuning ratio becomes almost independent of the number of inputs. Further, if the inputs comprise two populations (with different gain and phase values at a given stimulus frequency), the largest tuning ratio is obtained when the larger population has a smaller gain. These findings are discussed in the context of known anatomical and physiological characteristics of innervation patterns of primary otolith afferents and their possible convergence onto vestibular nuclei neurons.

Hearing↗
PubMed1994

Response properties of single units in areas of rat auditory thalamus that project to the amygdala. II. Cells receiving convergent auditory and somatosensory inputs and cells antidromically activated by amygdala stimulation.

The purpose of this study was to further our understanding of the contribution of auditory thalamoamygdala projections to conditioned emotional memories formed when auditory and noxious somatosensory stimuli are associated. Single unit activity was recorded in the acoustic thalamus of chloral hydrate-anesthetized rats in response to auditory (white noise, clicks, tones) and somatosensory (foot-shock) stimulation. The thalamic areas focused on were the medial division of the medial geniculate body (MGm), the suprageniculate nucleus (SG), and the posterior intralaminar nucleus (PIN), thalamic areas that receive inputs from both the inferior colliculus and the spinal cord and that project to the lateral nucleus of the amygdala (AL). For comparison, recordings were also made from the specific thalamocortical relay nucleus, the ventral division of the medial geniculate body (MGv), which receives projections from the inferior colliculus but not from the spinal cord. Auditory but not somatosensory responses were recorded from MGv, while both auditory and somatosensory responses were frequently found in MGm, PIN, and SG. In these areas, convergent auditory and somatosensory responses were more frequently found rostrally than caudally. Within a thalamic subregion, the acoustic response properties of the convergence cells were not different from the response properties of unimodal auditory cells. Some cells that responded to somatosensory but not auditory stimuli showed a potentiated response when tested with simultaneous presentation of auditory and somatosensory stimuli. In some studies, thalamic cells that project to the amygdala were antidromically activated by stimulation of the AL. Consistent with anatomical tracing results, antidromically activated cells were found in MGm, PIN, and SG, but not in MGv. Antidromically activated cells were more likely to respond to auditory stimuli than to somatosensory stimuli, but unimodal somatosensory and convergence cells were also found. These findings, which provide the first characterization of acoustic response properties of multimodal cells in the auditory thalamus and of cells in the auditory thalamus that project to amygdala, suggest insights into the emotional functions of the thalamoamygdala pathway.

Acoustic Stimulation↗
PubMed1980

Development of receptive field properties of retinal ganglion cells in kittens raised with a convergent squint.

The effects on retinal ganglion cell receptive fields of rearing kittens with convergent squint, surgically induced on the 12th post-natal day, were investigated by utilizing the extracellular single unit recording technique. The data revealed that responses of cross-eyed cat ganglion cells to contrast reversal stimuli were severely depressed and the retinal region exhibiting the best responses varied according to the degree of convergent misalignment of the eyes displayed by each animal. Receptive field sizes of X-type (but not Y-type) units located within 10 degrees of the area centralis of cross-eyed cats were significantly larger than those in normally reared cats. Finally, the encounter rate for units exhibiting non-linearity of spatial summation (Y-type) were much lower in cross-eyed cats. The results suggest developmental alterations in the retinal neurophysiology of common cats reared with a large convergent squint.

Animals↗
PubMed1979

Organization of the convergence in the intermediate cerebellar nuclei of somatosensory receptive fields with motor cortical-evoked responses.

The convergence in the intermediate cerebellar nuclei of somatosensory inputs with those from the motor cortex was investigated in cats (1) by examining with natural stimulation the receptive field of nuclear neurons, and (2) by determining the response of the same neurons to stimulation of motor cortical sites which had been identified by microstimulation-evoked movements. Of 196 neurons studied, a response to natural stimulation could be identified in 143, more than half of which (83) were driven by passive movement of one or two joints. The predominant response to cortical microstimulation was a suppression of discharge, although the suppression was sometimes preceded by a weak facilitation or interrupted by a brief but strong facilitation. A pattern of convergence was identified in which 72% of those cells driven by passive joint movement in one direction were suppressed by stimulation of the cortical site from which movement could be evoked in the opposite direction. A model based on this convergence is proposed.

Afferent Pathways↗
PubMed1976

Integration in descending motor pathways controlling the forelimb in the cat. 2. Convergence on neurones mediating disynaptic cortico-motoneuronal excitation.

With intracellular recording from forelimb motoneurones the spatial facilitation technique has been used to investigate interaction between descending pathways and forelimb afferents. As previously shown for the hindlimb, pyramidal volleys effectively facilitate interneuronal transmission in reflex pathways from different primary afferents. Evidence is presented suggesting disynaptic excitation from corticospinal fibres of interneurones in the reciprocal Ia inhibitory pathway. Interneurones of other reflex pathways from group I muscle afferents recieve monosynaptic pyramidal excitation. During pyramidal facilitation volleys in cutaneous afferents may evoke PSPs in motoneurones after a central delay of 1.3 ms suggesting that the minimal linkage is disynaptic. Information regarding convergence on the neurones intercalated in the disynaptic cortico-motoneuronal pathway was obtained by investigating the effect from primary afferents and from other descending pathways on the disynaptic pyramidal EPSPs. Volleys in cutaneous and group I muscle affferents facilitate transmission in the disynaptic cortico-motoneuronal transmission with a time course showing oligosynaptic (probably monosynaptic) action the intercalated neurone. Rubrospinal volleys likewise effectively facilitate disynaptic cortico-motoneuronal pathway with a time course showing oligosynaptic (probably monosynaptic) action on the intercalated neurone. Rubrospinal volleys likewise effectively facilitate disynaptic cortico-motoneuronal transmission with a time course showing monosynaptic action on the intercalated neurone. Spatial facilitation experiments involving three tests revealed that those intercalated neurones which receive convergent monosynaptic excitation from corticospinal and rubrospinal fibres are excited also from cutaneous forelimb afferents. Disynaptic cortico-motoneuronal transmission was also monosynaptically facilitated by stimuli in the dorsal mesencephalic tegmentum probably activating tectospinal fibres. Disynaptic, presumed tectospinal EPSPs were facilitated from cutaneous forelimb afferents. The convergence onto the neurones intercalated in the disynaptic excitatory cortico-motoneuronal pathway suggests that these neurones integrate the activity in different descending pathways and primary forelimb afferents.

Animals↗
PubMed1983

Convergence of sensory inputs upon projection neurons of somatosensory cortex: vestibular, neck, head, and forelimb inputs.

Cortico-cortical neurons and pyramidal tract (PT) neurons of the cat cerebral cortex were tested for convergent inputs from electrically stimulated vestibular, neck, head and forelimb nerves. Neurons were recorded within forelimb and vestibular projection regions of cortical area 3a. Consideration was given to both suprathreshold and subthreshold inputs. Neither vestibular, neck nor head inputs were detected in the forelimb region of area 3a. In contrast, within the vestibular projection region of area 3a, 43% (6/14) of the cortico-cortical neurons and 63% (24/38) of the PT neurons received excitatory vestibular input. Inputs from the skin of the pinna (greater auricular nerve) were detected only for PT neurons (66%, 25/38). No inputs were detected from afferent nerves supplying the dorsal neck muscles biventer cervicis and complexus. Cortico-cortical and PT neurons receiving vestibular input also received convergent inputs originating from forelimb group I deep and low threshold cutaneous afferent fibers. Further, one half of the PT neurons with vestibular input (12/24) received input from three somatic sources: forelimb group I deep, forelimb low threshold cutaneous and greater auricular (head) nerves. The input connectivities suggest a role for these projection neurons of somatosensory cortex in the coordination of head and forelimb movements. The convergence of vestibular information with somatic input from the forelimb implies that vestibular-influenced neurons of area 3a projecting to the motor cortex or through the pyramidal tract would signal head position or movement with respect to proprioceptive feedback from the limbs.

Afferent Pathways↗
PubMed1987

An analysis of potentially converging inputs to the rostral ventral thalamic nuclei of the cat.

Potentially convergent inputs to cerebellar-receiving and basal ganglia-receiving areas of the thalamus were identified using horseradish peroxidase (HRP) retrograde tracing techniques. HRP was deposited iontophoretically into the ventroanterior (VA), ventromedial (VM), and ventrolateral (VL) thalamic nuclei in the cat. The relative numbers of labeled neurons in the basal ganglia and the cerebellar nuclei were used to assess the extent to which the injection was in cerebellar-receiving or basal ganglia-receiving portions of thalamus. The rostral pole of VA showed reciprocal connections with prefrontal portions of the cerebral cortex. Only the basal ganglia and the hypothalamus provided non-thalamic input to modulate these cortico-thalamo-cortical loops. In VM, there were reciprocal connections with prefrontal, premotor, and insular areas of the cerebral cortex. The basal ganglia (especially the substantia nigra), and to a lesser extent, the posterior and ventral portions of the deep cerebellar nuclei, provided input to VM and may modulate these cortico-thalamo-cortical loops. The premotor cortical areas connected to VM include those associated with eye movements, and afferents from the superior colliculus, a region of documented importance in oculomotor control, also were labeled by injections into VM. The dorsolateral portion of the VA-VL complex primarily showed reciprocal connections with the medial premotor (area 6) cortex. Basal ganglia and cerebellar afferents both may modulate this cortico-thalamo-cortical loop, although they do not necessarily converge on the same thalamic neurons. The cerebellar input to dorsolateral VA-VL was from posterior and ventral portions of the cerebellar nuclei, and the major potential brainstem afferents to this region of thalamus were from the pretectum. Mid- and caudo-lateral portions of VL had reciprocal connections with primary motor cortex (area 4). The dorsal and anterior portions of the cerebellar nuclei had a dominant input to this cortico-thalamo-cortical loop. Potentially converging brainstem afferents to this portion of VL were from the pretectum, especially pretectal areas to which somatosensory afferents project.

Afferent Pathways↗
PubMed1987

Convergent inputs from articular, cutaneous and muscle receptors onto ascending tract cells in the cat spinal cord.

Responses were recorded from 160 ascending tract cells in segments L4 to L6 of the spinal cord in chloralose anaesthetized, spinalized cats. The tract cells were identified by antidromic activation following stimulation of pathways in the lateral and ventral funiculi at the level of the spinal cord transection at the thoracolumbar junction. Axonal conduction velocities ranged from 9 to 114 m/s. A sample of 152 of the neurones examined could be subdivided according to the distribution of their receptive fields into 49 cells activated just from receptors located in skin ("s" cells), 17 neurones excited by receptors in deep tissues ("d" cells), 15 units with a convergent input from receptors in skin and deep tissues ("sd" cells), and 25 neurones with a convergent input from the knee joint and either skin ("sj" cells), deep tissues ("dj" cells) or both ("sdj" cells). No receptive fields could be demonstrated for the remaining 46 neurones. "S" and "sj" cells were found almost exclusively in the dorsal horn, whereas many "d", "sd", "sdj" and "dj" units were in the ventral horn. Almost all of the cells that lacked receptive fields were in the ventral horn or intermediate grey. Ninety-one of 158 cells (56%) demonstrated no background activity. Of these, 43 cells (27%) lacked receptive fields. Many of the silent neurones were in the ventral horn, but some were in the dorsal horn. Of 25 cells having knee joint input, 18 (72%) had background activity. All of the neurones that had a receptive field in the knee joint also had a convergent input from receptors in other tissues. In 3 cases, there was a receptive field in the skin over the foot ("sj" cells). For 16 cells, receptive fields included not only the knee joint but also skin and deep tissue ("sdj" cells). Usually, the cutaneous receptive field was near the knee joint, but sometimes it was remote, such as on the foot. The deep receptive fields were chiefly in the muscles of the thigh and/or leg. For 6 "dj" cells, the receptive fields included not only the knee joint but also deep fields like those of "sdj" cells. Cutaneous receptive fields were classified as "low threshold" (cells excited best by innocuous intensities of mechanical stimulation), "wide dynamic range" (cells activated by weak mechanical stimuli, but the best responses were to noxious stimuli) or high threshold (innocuous stimuli had little effect, but noxious mechanical stimuli produced a vigorous discharge).(ABSTRACT TRUNCATED AT 400 WORDS)

Afferent Pathways↗
PubMed1976

Convergence of genetic compositions assuming infinite population-size and overlapping generations.

The assumptions for the model treated in this paper are based on a population of hypothetically infinite size, which has reached its optimum density within a limited habitat. The aim has been to derive sufficient conditions for the genetic composition of a population to converge to a limit if generations overlap and time is measured in discrete intervals. Trivially the genetic composition does not change if at the starting point of time the compositions within all age-classes are the same; otherwise global convergence of the age-class distributions implies uniform convergence of the genetic compositions within the single age-classes if mating takes place between at least two age-classes, or within the first age-class only. Excluding age-class 1 mating within one age-class only results in periodical change of genetic compositions.

Age Factors↗
PubMed1996

Influence of pulse repetition frequency and high pass filter on color Doppler maps of converging flow in vitro.

Assessment of regurgitant flow by the flow convergence method is based on reading absolute velocities from color Doppler maps. Velocity overestimation by high pass filtering above 100 Hz has been reported. An extremely low filter, however, is impracticable in patients. A ratio of pulse repetition frequency (PRF)/filter of 10/1 usually results in good quality color maps as judged visually. We studied in vitro the influence of RPF and filter on the absolute velocities within color maps of the flow convergence, keeping PRF/filter at 10/1. The color maps were also compared with computerized flow simulations. Flow across different orifice plates was scanned using two different setups for each flow condition: low velocity setup (PRF 600-2500 Hz, filter 50-300 Hz) and high (PRF 1500-6000 Hz, filter 200-600 Hz). From the color maps, velocity profile curves were read along the flow center line across the flow convergence. The high velocity setup provided artefact-free color maps at a distance d = 2-4 through 8-11 mm to the orifice, the low setup at d = 6-8 through 18 mm. Within the overlapping range (d = 6-8 through 8-11 mm), the resulting curves showed no significant differences in local velocity, with a slight trend towards higher velocities with the high velocity setup (2.2-2.9%). The simulations agreed well with color Doppler except for slightly lower values at d > 10-12 mm. Changes in PRF and filter have no significant influence on the absolute velocities displayed within color maps as long as PRF/filter is kept close to 10/1.

Blood Flow Velocity↗
PubMed1994

A comparison of four PTSD measures' convergent validities in Vietnam veterans.

We compared the convergent validities of four commonly used post-traumatic stress disorder (PTSD) measures in 80 help-seeking Vietnam veterans by contrasting their intercorrelations. When scored as continuous severity or frequency measures, the Mississippi Scale for Combat-related PTSD's and the Post-Traumatic Stress Disorder Interview's (PTSD-I's) concordances with other measures were similar to one anothers' and generally larger than those of either the Diagnostic Interview Schedule (DIS) PTSD module or the MMPI PTSD scale. However, when used only to identify stress disorder's presence or absence, the four techniques' concordances were nearly identical. This suggested that the four measures have similar convergent validities when used simply to identify PTSD, but that the PTSD-I and Mississippi scale offer better convergent validity than the MMPI or DIS instruments when used as severity measures.

Adult↗