ADHD Endophenotypes in Caribbean Families.

Objective: The aim of this study is to contrast the genetics of neuropsychological tasks in individuals from nuclear families clustering ADHD in a Caribbean community. Method: We recruited and clinically characterized 408 individuals using an extensive battery of neuropsychological tasks. The genetic variance underpinning these tasks was estimated by heritability. A predictive framework for ADHD diagnosis was derived using these tasks. Results: We found that individuals with ADHD differed from controls in tasks of mental control, visuospatial ability, visuoverbal memory, phonological and verbal fluency, verbal and semantic fluency, cognitive flexibility, and cognitive ability. Among them, tasks of mental control, visuoverbal memory, phonological fluency, semantic verbal fluency, and intelligence had a significant heritability. A predictive model of ADHD diagnosis using these endophenotypes yields remarkable classification rate, sensitivity, specificity, and precision values (above 80%). Conclusion: We have dissected new cognitive endophenotypes in ADHD that can be suitable to assess the neurobiological and genetic basis of ADHD.

Linkage and association analysis of ADHD endophenotypes in extended and multigenerational pedigrees from a genetic isolate.

Attention-deficit/hyperactivity disorder (ADHD) is a heritable, chronic, neurodevelopmental disorder with serious long-term repercussions. Despite being one of the most common cognitive disorders, the clinical diagnosis of ADHD is based on subjective assessments of perceived behaviors. Endophenotypes (neurobiological markers that cosegregate and are associated with an illness) are thought to provide a more powerful and objective framework for revealing the underlying neurobiology than syndromic psychiatric classification. Here, we present the results of applying genetic linkage and association analyses to neuropsychological endophenotypes using microsatellite and single nucleotide polymorphisms. We found several new genetic regions linked and/or associated with these endophenotypes, and others previously associated to ADHD, for example, loci harbored in the LPHN3, FGF1, POLR2A, CHRNA4 and ANKFY1 genes. These findings, when compared with those linked and/or associated to ADHD, suggest that these endophenotypes lie on shared pathways. The genetic information provided by this study offers a novel and complementary method of assessing the genetic causes underpinning the susceptibility to behavioral conditions and may offer new insights on the neurobiology of the disorder.

[Diagnostic validity of attention deficit/hyperactivity disorder: from phenomenology to neurobiology (I)]. / Validez del diagnostico de trastorno por deficit de atencion/hiperactividad: de lo fenomenologico a lo neurobiologico (I).

The diagnostic criteria for the attentional deficit hyperactivity disorder (ADHD), were defined by the American Psychiatric Association in the Diagnostic and Statistical Manual of Mental Disorders fourth version (DSM-IV) and World Health Organization in the ICD-10. The American Psychiatric Association used an internal validity analysis to select specific behavioral symptoms associated with the disorder and to build five cross-cultural criteria for its use in the categorical diagnosis. The DSM has been utilized for clinicians and researchers as a valid and stable approach since 1968. We did a systematic review of scientific literature in Spanish and English, aimed to identify the historical origin that supports ADHD as a psychiatric construct. This comprehensive review started exploring the concept of minimal brain dysfunction, hyper-activity, inattention, impulsivity since 1932 to 2011. This paper summarize all the DSM versions that include the definition of ADHD or its equivalent, and it point out the statistical and methodological approach implemented for defining ADHD as a valid epidemiological and psychometric construct. Finally the paper discusses some considerations and suggestions for the new versions of the manual.

[Attention deficit hyperactivity behavioral phenotype dimensions of adults from Antioquian families using the Wender-Utah Scale -Spanish version]. / Dimensiones del fenotipo conductual del trastorno por déficit de atención/hiperactividad en adultos de familias antioqueñas utilizando la escala Wender-Utah en Español.

INTRODUCTION: The Wender-Utah Rating Scale (WURS) has been used for retrospective screening of attention deficit hyperactivity disorders (ADHD) symptoms and its comorbidities. AIM: To establish the ADHD behavioral phenotype dimensions of adults from 140 Antioquian families with genetic segregation for ADHD diagnosis, using the WURS -Spanish version. SUBJECTS AND METHODS: 392 adults from both genders, belonging to nuclear and multigenerational families with one or more ADHD affected members were selected. The Composite International Diagnostic Interview (CIDI) for mental disorder was administered to establish the gold standard diagnosis of ADHD through the long life. All participants fulfill the WURS. Exploratory and confirmatory factor analyses were done to determine the behavioral dimensions of the ADHD phenotype. RESULTS: A factor structure of four dimensions was derived, measuring behavioral decontrol, hyperactivity, inattention and anxiety, and which explained the 60% of the total variance. CONCLUSIONS: The behavioral adult ADHD phenotype in the Antioquian families was conformed by four dimensions, which could be used in heritability and linkage future studies.

[Analysis of intrusive errors in a memory test as possible pre-clinical marker of familial Alzheimer disease, in E280A presenilin-1 mutation carrier]. / Analisis de las intrusiones en una prueba de memoria como posible marcador preclinico de enfermedad de Alzheimer en portadores de la mutacion E280A de la presenilina-1.

INTRODUCTION: Intrusive errors in verbal memory tests could be considered as a preclinical marker of familial Alzheimer disease (AD). AIMS. To analyze and to compare the number and types of intrusive errors in the CERAD verbal memory test, administered to a genealogy of affected by familial AD, with E280A presenilin-1 mutation. PATIENTS AND METHODS: Sample was constituted by 30 asymptomatic non-carriers (ANC), 39 non-demented carriers (NDC) and 21 demented carriers (DC). CERAD verbal memory test was administered to the sample. Comparisons, with non parametric Kruskal-Wallis' analysis, were done. RESULTS: NDC participants presented more intrusive errors than ANC group in the first and second trials and in the delay recall of the memory task; also they had more intrusive errors than the DC patients in intrusive errors of the first trial and delay recall of the same task. The ANC and DC groups had significantly more intrusions only in third trial. CONCLUSION: Intrusive errors could be considered as a cognitive preclinical marker for familial AD.

[Behavioural and neuropsychological characteristics of children of both sexes, between 6 and 11 years of age, with attention deficit hyperactivity disorder]. / Características conductuales y neuropsicológicas de niños de ambos sexos, de 6 a 11 años, con trastorno por déficit de atención/hiperactividad.

INTRODUCTION: Attention deficit hyperactivity disorder (ADHD) gives rise to behavioural and neuropsychological alterations. AIMS: The purpose of this study is to compare the behavioural and neuropsychological skills of 6 to 11-year-old children of both sexes, who have been diagnosed with ADHD, with that of a control group. SUBJECTS AND METHODS: From a total of 1200 schoolchildren, whose parents and teachers answered a brief ADHD screening survey, we selected 112 participants who were then submitted to a psychological clinical interview and a neurological examination in order to assign them to one of three groups: combined-type ADHD, inattentive ADHD and a control group. Behaviour was assessed by applying the Conners' Rating Scales and the multidimensional behaviour survey. Cognitive capacities were assessed by applying a neuropsychological battery for attention, memory, visuomotor and verbal skills, and executive functions. Groups were compared by means of a Kruskal-Wallis non-parametric univariate analysis of variance. In the case of pairs of groups, the Mann-Whitney U test was employed. RESULTS: The behavioural scales showed greater alterations in the case groups, with more problems in the combined-type ADHD group. Neuropsychologically, significantly lower performances were observed in the ADHD groups in sustained attention, executive function, semantic and phonological fluency tests. CONCLUSIONS: Behavioural disorders are the most apparent in ADHD. The neuropsychological alterations that were found were similar to those reported in other studies conducted in Colombia.

[Prevalence of mild cognitive impairment, amnestic-type, in a Colombian population]. / Prevalencia de deterioro cognitivo leve de tipo amnésico en una población colombiana.

INTRODUCTION: Mild cognitive impairment (MCI) is a clinical syndrome that presents with memory disorders, normal general cognition, and no compromise of activities of daily living or dementia. Its diagnosis has important clinical implications, since it behaves as a possible predictor of cognitive disorders that would suggest the onset of dementia. Amnestic-type MCI is considered to be a stage prior to Alzheimer-type dementia. The prevalence of MCI varies from 1-29% and the existence of this diagnosis implies a risk of presenting dementia at 12% per year. AIM: To establish the prevalence of amnestic-type MCI in a group of persons over the age of 50 years from the Valle de Aburra. PATIENTS AND METHODS: The sample was made up of 848 participants of both genders, over 50 years old, who lived in the metropolitan area of Medellin and had different socioeconomic and educational levels. Amnestic MCI was diagnosed according to the criteria proposed by the American Academy of Neurology. RESULTS: Prevalence of amnestic MCI was 9.7%, and was more predominant in males (p = 0.01) than in females. The prevalence was significantly lower in the group with more than 12 years of schooling (p < 0.05), and no significant differences in the prevalence were found in relation to age or economic status. CONCLUSION: The prevalence of amnestic MCI, 9.7%, found in our study is within the range reported by other researchers.

[Validity and reliability of the CERAD-Col neuropsychological battery]. / Validez y fiabilidad de la batería neuropsicológica CERAD-Col.

INTRODUCTION: Alzheimer's disease (AD) is an important public health problem due to its disabling character and high individual, familial and social costs. The CERAD neuropsychological battery has been widely used for evaluation and diagnosis of the cognitive deficit associated with AD. This instrument has been adapted to the Colombian culture (CERAD-Col) for the Neurosciences Group. SUBJECTS AND METHODS: A study was carried out to establish the validity and reliability of the CERAD-Col in Colombian, Spanish-speaking individuals aged 50 years or more. It included 151 controls and 151 AD patients. Controls were selected from a convenience sample of 848 adults aged 50 years or more. The construct validity was determined in three ways: 1) factorial analysis; 2) correlation with the functional scales FAST and GDS (convergent-type validity) and, 3) comparison between the two groups. Internal consistency was determined by means of Cronbach's alpha coefficient. RESULTS: Three factors -memory, language and praxis- explained 88% of the total variance. Moderate but statistically significant correlations were found between neuropsychological tests and functional scales. Internal consistency and test-retest reproducibility were high. The AD group exhibited significantly lower scores (p < 0.05) than the control one. CONCLUSION: CERAD-Col is valid and reliable for the diagnosis of AD in Colombian Spanish-speaking population aged 50 years or more.

[Specific impaired language development: a selective or generalised cognition problem]. / Trastorno específico del desarrollo del lenguaje: problema selectivo o generalizado de la cognición.

INTRODUCTION: Specific developmental language disorder (SDLD) is a diagnostic entity in which language is expected to be the only cognitive function that is affected. Nevertheless, difficulties in other cognitive functions may also appear, either because the language disorder is an expression of an underlying condition or because the retarded language development gives rise to cognitive deficits in general. AIM: To determine whether there are any differences in the cognitive performance of children with SDLD and that of children who have developed normally. SUBJECTS AND METHODS: The study involved a sample of 51 children with SDLD, aged between 6 and 16 years, and 49 children in a control group, who were paired by chronological age, sex and socioeconomic level. Verbal cognitive capacity, attention, memory, visual-constructional and executive functioning were all evaluated. RESULTS: Statistically and clinically significant differences were found in the verbal-type skills, such as language comprehension and verbal cognitive capacity, which showed effect sizes of -1.31 and -1.33, respectively. In the other functions that were assessed, the performance of the SDLD group was slightly lower than that of the control group, but with no clinically significant differences. CONCLUSION: These findings show that the group of children with SDLD was well selected, since the only differences between the two groups involve linguistic aspects; moreover, this evidence supports the idea that language and other cognitive functions are relatively independent and that a language disorder would only generate an unspecific general effect in the other cognitive functions.

[A description of semantic memory performance in a sample of the Antioquian population]. / Descripción del desempeño en memoria semántica en una muestra de la población antioqueña.

INTRODUCTION: Available treatments for Alzheimer disease allow that early diagnosis become an important issue, because treatment only are useful during the earliest stage, especially during the mild cognitive impairment (MCI), when the most of the cognitive function is preserved. AIM: To observe the performance on a shortened version of a Semantic Cue Recall Memory Test (SCRMT) from a group of adult aged over 50 years old, living in Medellin city and with dementia of Alzheimer type (DAT). SUBJECTS AND METHODS: The sample was constituted by 30 patients with DAT, 30 with MCI, and 59 healthy controls, which were matched by socio economic strata and school achievement. The SCRMT was administered to the sample. For the analyses two groups of age (50-69 and over 70 years) were conformed. RESULTS: Comparisons statistically significant differences between the groups (p < 0.05). The scores were not significant affected by age. A combination of low scores with the presence of intrusions on the free, immediate cue, and delay cue recalls suggested the diagnosis of DAT, which allow recommending a complete neuropsychological assessment. Statistically significant differences were preserved when the groups were divided by age. The effect of the gender could not determine because the small size of the male sample. CONCLUSION: The shortened version of the SCMRT would appear be useful for the DAT diagnosis.

[Phonological awareness in child with attention deficit disorder without learning disabilities]. / Conciencia fonoloóica en niños con trastorno de la atención sin dificultades en el aprendizaje.

INTRODUCTION: Phonological awareness problems have been reported in children with attention deficit/hyperactivity disorder (ADHD). However, other researches found that phonological awareness problem appear only in children with learning disabilities (LD). OBJECTIVE: To analyze the performance on phonological awareness tasks of children aged 7 to11 years with ADHD combined type (ADHD/+H), and inattentive type (ADHD/-H) compared with one control group. PATIENTS AND METHODS: A non-randomized sample consisting of 96 children of both genders was selected. Children were attending to school in Medellin, Colombia. The sample was classified into three groups of 32 participants: ADHD/+H, ADHD/-H and control. LD was excluded using a standardized questionnaire for teachers (CEPA). Groups were sorted using a T score (3) 60 for cases and T score pound 50 for controls on a standardized questionnaire with DSM-IV-ADHD criteria, and on an ADHD-DSM-IV checklist. The performances of the three groups on phonological awareness tasks, as auditory discrimination, visual recognition, sequential repetition, oral segmentation, syllable inversion, similar words reading and writing, and pseudo-words reading and writing, were compared. RESULTS: Differences between ADHD and control children on phonological awareness tasks scores were not found. CONCLUSION: Children with ADHD without LD performed similarly to controls on phonological awareness tasks.

[Attention and executive function tests components in attention deficit/hyperactivity children]. / Componentes de las pruebas de atención y función ejecutiva en niños con trastorno por déficit de atención/hiperactividad.

INTRODUCTION: It has been suggested that children with attention deficit/hyperactivity disorder (ADHD) have problems in attention and executive functions. A factor analysis showed that ADHD children had a different factor structure of the executive functions when they were compared with controls. AIM. To determine the factor structure of attention and executive functions in a group of ADHD children compared with a group of controls. SUBJECTS AND METHODS: 249 ADHD children and 372 controls of both genders, aged 6 to 11 years old, and from the different socio economic strata of Medellín city, were selected. Attention --Mental Control and Auditory Continuous Performance Test (ACPT)-- and executive functions --Phonologic and Semantic Verbal Fluency (FAS)--, and a shortened version of the Wisconsin Card Sorting Test (WCST) were assessed in both groups. Factor analyses were developed with principal components procedure were developed for each group and the total sample, using principal component procedure with orthogonal rotation. RESULTS: Stable factor structures were found for each group and for the total sample. The general factor structure was constituted by three independent factors: 1- Categorization, 2- Verbal fluency and verbal sustained attention, and 3- Cognitive flexibility. This factor structure explained 74.9% of the variance. CONCLUSION: The factor structures suggested that the components of attention and executive functions are similar for ADHD and control groups. The differences between groups would be quantitative.

[Specific developmental language disorder: a theoretical approach to its diagnosis, aetiology and clinical symptoms]. / Trastorno específico del desarrollo del lenguaje: una aproximación teórica a su diagnóstico, etiología y manifestaciones clínicas.

AIM: This article presents an updated review about the definition, diagnostic criteria, classifications, etiology and the evolution of the specific language impairment (SLI). DEVELOPMENT: The specific language impairment is characterized by a developmental language delay and an impaired language, that persist over time and it is not explained by sensorial, motor and mental disabilities, neither by psycopathological disorders, socio-emotional deprivation, nor brain injury. The diagnosis is based on exclusional criteria. Some researchers propose different classifications considering the children performance in language comprehension and language production. Genetical linkage to the FOXP2 gen in the SPCH1 region of the chromosome 7 and to the chromosomes 13, 16 y 19 has been reported. The neuroimage studies have shown alterations in the volume and perfusion of some brain structures related to language. The manifestations of SLI may change during the development of the children and may disturb the self-esteem, the academic performance and the social abilities. CONCLUSIONS: The variability in the linguistic and cognitive performance, and the variety in the etiological findings in children with SLI, don't allow to settle the affected population as an homogeneous group. Different theoretical positions have emerged as a consequence of this condition.

[Performance of carriers and non-carriers of the E280A mutation for familial Alzheimer's disease in a naming test]. / Desempeño de portadores y no portadores de la mutación E280A para enfermedad de Alzheimer familiar en una prueba de denominación.

INTRODUCTION: Early preclinical diagnosis is the greatest challenge faced by researchers into dementia. Cognitive, neuroanatomical, neurophysiological and genetic markers have been reported. One of the preclinical cognitive markers is anomia and it is often assessed using visual naming tests. AIMS: The aim of this study was to analyse the type of mistakes made in a visual naming test in a group of carriers and non-carriers of the E280A PS1 mutation. PATIENTS AND METHODS: The sample was made up of 91 participants who were genotyped for the E280A PS1 mutation and divided into three groups: non-carriers (n = 30), asymptomatic carriers (n = 39) and sick carriers (n = 22). Selection was performed using the Minimental and the Fast and EDG scales and mistakes in the CERAD naming test were classified. The types of mistakes taken into account were: no answer, visual, semantic, phonological, the whole for the part, and not related. RESULTS: There is a significant difference in the number of semantic errors between non-carriers and asymptomatic carriers; on comparing the three groups, no statistically significant differences were found in visual mistakes. CONCLUSIONS: Visual mistakes are a general characteristic, even in healthy subjects and, therefore, these errors did not provide any information that could be used to classify patients with or without dementia. Semantic mistakes can be considered as being a preclinical sign in familial Alzheimer's disease (FAD). Both visual and auditory naming tests must be applied when evaluating patients with FAD.

[Neuropsychological and behavioral profiles of children with attention deficit/hyperactivity disorder from cali, colombia]. / Perfiles neuropsicológicos y conductales de niños con trastorno por déficit de atención/hiperactividad de Cali, Colombia.

INTRODUCTION: Several studies have found neuropsychological and behavioral disorders in children with attention deficit/hyperactivity disorder (ADHD), which have been explained as an executive dysfunction. OBJECTIVE: To describe and compare children with ADHD and a control group. PATIENTS AND METHODS: 79 seven to eleven-year-old children were selected and grouped according to ADHD DSM IV criteria and the T scores on a ADHD checklist. They were classified as predominantly inattentive (n=19), combined (n=24) and control (n=36) groups. Age, gender, socio economic status and intellectual quotient (>85) were statistically controlled. Neuropsychological functions were assessed with a child neuropsychological battery, and the behavioral dimensions were evaluated with the BASC's questionnaires, Conner's parents (CPRS) and teachers (CTRS) rating scales, and with a questionnaire for oppositional defiant (ODD) and conduct (CD) disorders. RESULTS: Statistically significant differences were found (P<0.01) in neuropsychological variables of mental control, continuous auditory performance, Rey's complex figure evocation and the Stroop's test. There were significant differences in the most BASC's internalizing and externalizing dimensions, so for the parents as for the teachers and self report questionnaire, and in the dimensions of CPRS, CTRS, ODD and CD questionnaires. CONCLUSION: Children with ADHD showed difficulties in sustained and selective attention, visual memory, inhibitory control, and they had behavioral disorders similar to those informed by previous studies.

[Perinatal factors associated with attention deficit/hyperactivity diagnosis in Colombian Paisa children]. / Factores perinatales asociados con la aparición del trastorno por deficiencia de atención en niños de la comunidad colombiana 'paisa'.

INTRODUCTION: Some perinatal factors have been associated with attention d ficit/hyperactivity disorder (ADHD). OBJECTIVE: To estimate the association between perinatal factor and ADHD diagnosis in school, aged 6 to 11 years, children from Medell n city (Colombia). PATIENTS AND METHODS: A randomized sample of 200 cases, 6 to 11 year old, with standardized ADHD diagnosis was selected. A randomized sample of 200 control children, 6 to 11 year old, was selected from a data base of 70 schools of Medell n city. The same diagnostic protocol was administered to controls. A questionnaire with questions about pregnancy, delivery an neonatal period was given to the mothers. Data were analyzed using cross tabulation and stepwise logistic multiple regression analyses. RESULTS: Miscarriage symptoms, premature delivery symptoms, severe flu attacks (cold with fever, without virus confirmation), tobacco abuse, alcohol abuse (to become drunk), minor congenital malformations, neonatal seizures and hospitalizations during newborn period were factors associated with ADHD diagnosis (p< 0.05). However, stepwise logistic multiple regression analysis selected a block of variables formed by premature delivery symptoms, severe flu attacks and neonatal seizures as significant perinatal risk factors (p< 0.01) for ADHD diagnosis.

[Prevalence of mental retardation in teenagers with dissocial conduct disorder]. / Prevalencia del retarso mental en adolescentes con trastorno disocial de la conducta.

INTRODUCTION: Prevalence of adolescents with conduct disorder (CD) has been calculated between 4 y 10%. OBJECTIVE: To estimate the prevalence of mental retardation in Colombian adolescent offenders, using the Wechsler Intelligence Scales for Children Revised (WISC R). PATIENTS AND METHODS: 106 male adolescent offenders with CD, aged 12 to 16 years, and attending to institutions of re education in Medell n Colombia were selected in a randomized approach. WISC R Hispanic version was administered to the sample, using 4 verbal (information, vocabulary, similarities and arithmetic) and 4 performance (Picture completion, block design, picture arrangement, and digit symbol) subtests for calculating verbal, performance and full scale IQs (VIQ, PIQ, and FSIQ), according to the manual instructions. RESULTS: 43 participants (40.6%) obtained a FSIQ < 70, then they were categorized as mild mental retardation. 34 offenders (32.1%) had a FSIQ between 70 and 84, then they were classified as people with borderline intellectual functioning, only 29 participants (27.4%) obtained a FSIQ over 85. CONCLUSION: 72.7% of the institutionalized adolescents offenders had low intellectual functioning, which may be interfere with the re education programs.

Utilidad de un cuestionario para rastreo del estres postraumatico en una poblacion colombiana / Use fulness of a screening questionnaire for post traumatic stress in a columbian population

Introducción. Las escalas para el diagnóstico del trastorno de estrés postraumático (TEPT) deben ser consistentes con los criterios del DSMIV y validarse para cada cultura. Objetivos. Validar una lista de síntomas (checklist) para el diagnóstico de TEPT en la población de un municipio colombiano semidestruido por un ataque de la guerrilla. Pacientes y métodos. Se seleccionó una muestra aleatoria, representativa y estratificada de 202 habitantes, mayores de 15 años, del municipio de San Joaquín (Santander, Colombia), dos años después de un ataque de la guerrilla. A los participantes se les hizo una entrevista clínica estructurada (SCID- I), basada en los criterios diagnósticos del DSM-IV para TEPT. 76 personas (37,6 por ciento) reunieron los criterios para TEPT y 126 (62,4 por ciento) se consideraron sin TEPT. A los dos grupos se les aplicó una lista de 24 síntomas de TEPT, calificados en una escala de 1 a 4. Resultados. La lista de síntomas tuvo una consistencia interna excelente (coeficiente alfa de Cronbach, 0,97). El grupo de TEPT obtuvo una puntuación de 70,4 ñ 22,9 y el grupo sin TEPT puntuó 37,2 ñ 13,7 (p< 0,0001). Un análisis discriminante mostró una capacidad de clasificación correcta del 88,6 por ciento (p<0,0001). La sensibilidad varió entre el 76,3 por ciento para un punto de corte de 51, hasta 81,6 por ciento para un corte en 45 puntos. La especificidad estuvo entre 71,4 por ciento para un corte en 45 y de 84,4 por ciento para un corte en 51. Conclusión. La lista de síntomas para TEPT tiene una excelente consistencia interna, una buena capacidad discriminante y buenos niveles de sensibilidad y especificidad

[Usefulness of a screening questionnaire for post traumatic stress in a Colombian population]. / Utilidad de un cuestionario para rastreo del estrés postraumático en una población colombiana.

INTRODUCTION: Rating scales for post traumatic stress disorder (PTSD) should be consistents with DSM IV criteria, and should be validate for each culture. OBJECTIVE: To validate a PTSD checklist in a Colombian little town population, which was semi destructed by a guerrilla attack. PATIENTS AND METHODS: A stratified, representative and randomized sample of 202 adult participants, aged over 15 year old, was selected from San Joaquin (Santander Colombia) two year after an guerrilla attack. A structured interview (SCID I), based on DSM IV criteria, was developed with each member of the sample. 76 participants (37.6%) met criteria for PTSD, and 126 (62.4%) were classified as non PTSD. A rating checklist with 24 symptoms of PTSD was applied by self report. Each item of the scale was scored 1 to 4. RESULTS: PTSD checklist had a reliability Cronbach s alpha coefficient of 0.97. PTSD group scored 70.4 22.9, and non PTSD 37.2 13.7 (p< 0.0001) on the PTSD checklist. A discriminant analysis found that the scale had a correctly classification capability of 88.6% (p< 0.0001). Sensibility was found between 76.3% for a cut off point of 51 and 81.6% for cut off point of 45. Specificity changed between 71.4% for a cut off point of 45 and 84.4% for a cut off point of 51. CONCLUSION: Checklist for PTSD had a high reliability, good discriminant capability, and good sensibility and specificity.