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Introduction. Cancer survivorship in Mexico is a research topic that is still in its infancy. No specific studies have been found on the needs of this population, meaning that there are no validated scales in the Mexican population measuring the needs of cancer survivors. Objective. To validate and adapt the Cancer Survivors' Unmet Needs survey, Spanish version (CaSUN-Mx) for use in the Mexican adult oncology population. Method. One hundred and eighty participants answered the questionnaire (CaSUN-S). For the analysis, the study was divided into three phases: content validity, construct validity, and internal consistency analysis. Results. The final version of the adapted questionnaire (CaSUN-Mx) has 34 items and one open question. It was divided into five factors with a total Cronbach's Alpha of .95 and a value of over .85, in all the subscales (psychological care, comprehensive and collaborative care, practical and information needs, and those associated with effects. Discussion and conclusion. The CaSUN-Mx questionnaire has content validity because it has been adequately linguistically and culturally adapted, and construct validity because of its factorial structure, and reliability, making it suitable for use in the Mexican adult oncology population. [ABSTRACT FROM AUTHOR]

Introduction. Increased rumination is associated with longer night-time sleep onset latency and poorer sleep quality and efficiency in people with insomnia symptoms. Objective. To validate the Diurnal Insomnia Symptoms Response Scale (DISRS) in a general population sample. Method. 102 participants (women = 67 and men = 35) comprising patients and relatives who attended an outpatient consultation at a health center in Mexico City were evaluated. The English-Spanish-English translation system was used by two Spanish-speaking experts on the subject, an independent bilingual expert translated the new version of the scale into English, which was then compared with the original. The following self-administered questionnaires were used to evaluate the convergent, discriminant validity of this tool: the Ruminative Response Scale (RRS), the Insomnia Severity Index (ISI), and Penn State Worry Questionnaire (PSWQ). Results. The internal consistency of the scale items was a = .93. Principal components factor analysis yielded three factors with an eigenvalue of greater than one, which together explain 59.5% of the variance. Correlations between the total DISRS score and the cognitive-motivational dimensions (r = .938, p < .01), negative state (r = .898, p < .01) and tiredness (r = .853, p < .01) were statistically significant. Insomnia symptoms (SCC = .89) outweighed worries (SCC = .33) and ruminant responses (SCC = .33) when discriminating between cases with low and high levels of rumination associated with insomnia symptoms. Discussion and conclusion. Our results suggest that the DISRS scale has adequate psychometric properties that make it valid and reliable for use with the Mexican population. [ABSTRACT FROM AUTHOR]

Introduction. Suicide attempts are the most predictive risk factor for suicide deaths. Most people who attempt suicide receive care from out-of-hospital Emergency Services (OES), where these requests are managed and classified. Objective. Validate the Emergency Coordination Center (ECC) classification for the detection of suicidal behavior requests. Method. A descriptive, cross-sectional study of requests to the ECC of Málaga (Spain) during 2013 and 2014 was conducted. To classify the requests, the authors considered the ECC categorization when answering the call and the clinical assessment of the healthcare professional when attending the person who had made the call at the scene, which was considered the reference standard. To analyze the validity of the ECC classification system, sensitivity, specificity, and positive and negative predictive values (PPV and NPV) were calculated. Results. The total number of requests for medical assistance analyzed was 112,599. The validity indicators of the classification system for suicidal behavior were sensitivity = 44.78%, specificity = 99.34%, PPV = 46.91% and NPV = 99.28%. Discussion and conclusion. The ECC classification system has a lower capacity to detect the presence of suicidal behavior and a higher capacity to identify its absence in the requests received. OES provide key information on suicidal behavior requests as they can be one of the first places people with this problem go to. It would therefore be extremely useful to improve the classification systems for requests related to suicidal behavior. [ABSTRACT FROM AUTHOR]

Introduction. The Childhood Autism Rating Scale (CARS) is an observational instrument for assessing autism. It is the most widely used instrument for the diagnosis of autism in Mexico. Objective. To study the psychometric properties in the Mexican population using DSM-IV and DSM-5 criteria. Method. This is an observational, cross-sectional study. Participants (N = 137) were 78.8% male, with an age range between 2 and 18 years, mean 8.5. Parents completed the M-CHAT, the ABC, the ADI-R, and semi-structured clinical interviews with DSM-IV. We inferred DSM-5 criteria by selecting atypical sensory items from the ABC. Results. The internal consistency for the total CARS items was α = .88. The concurrent validity of the CARS and the DSM-IV criteria showed a Spearman coefficient of correlation of rs = .62. The convergent validity with the ADI-R showed moderate correlations, rs = .32 to .61, with the DSM-IV k = .33 and DSM-5 k = .36. The concordance with the DSM-IV and DSM-5 was 71% and 84.5%, sensitivity was 58.1% and 46-7%, and specificity 76.6% and 90.5%, respectively. The discriminant analysis showed that the CARS correctly classified 97% of children with autism, 70% with pervasive developmental disorders not otherwise specified (PDD-NOS), and 12.5% with Asperger's syndrome. Discussion and conclusion. The Mexican version of the CARS is a valid and reliable instrument for diagnosing autism in Mexican children and adolescents. [ABSTRACT FROM AUTHOR]

Introduction. The Beck Depression Inventory (BDI-IA) is the most widely used instrument for assessing depression symptoms. Although it has been validated in the Mexican population, it has not been tested in people living with HIV (PLWH), who tend to have symptoms difficult to distinguish from those associated with viral infection. Objective. We obtained the psychometric properties, sensitivity, specificity, and cut-off points to distinguish between a depressive episode, adjustment disorder and no symptoms. Method. Prospective study with 2,022 PLWH (88% men), who completed the BDI-IA between 2016 and 2017. Subjects had a mean age of 31.9 ± 9.3 years, with 12.0 ± 5.6 years of schooling, and 4.5 ± 4.3 years since diagnosis. The differentiation of items, internal consistency, factor analysis, and calculation of sensitivity and specificity were tested. Results. A Cronbach's alpha coefficient of .91 was obtained. Through factorial analysis with orthogonal rotation (average intercorrelations r = .40, KMO .929), we obtained three factors: general factor of depression, somatic, and cognition, which explained 39.7%, 6.01%, and 5.49% of the variance, respectively. Only the items in the first factor (the short version with 12 items) were tested. With a cut-off point of 11, it had 85.5% sensitivity and 76% specificity [(AUC) = .865, 95% CI [.83, .90], p < .001], and distinguished major depressive disorder from cases without mental symptoms. Discussion and conclusion. We show that the short version of the BDI-IA is reliable, valid, sensitive, and specific for evaluating depression symptoms comorbid with HIV infection. [ABSTRACT FROM AUTHOR]

Introduction. Parenting practices refer to specific behaviours used by parents and caretakers of children to guide childhood development and socialization goals. These practices are associated with children's health, psychological, and physical development. Objective. To determine the psychometric properties of the Parenting Practices Inventory (PPI) among a group of child caregivers in Mexico City. Method. The PPI was applied to 443 caregivers of children and adolescents, who attended a general health care centre in Mexico City. For the psychometric evaluation of the instrument, the full distribution and discrimination of the items was analysed first. Then, the validity of the construct was tested through an exploratory factor analysis and a confirmatory analysis with structural equation modelling. Results. The internal consistency of the PPI showed α = .867 and 41.25% of variance explained for all four dimensions of interest. The confirmatory factor analysis showed that the model had goodness of fit. It included twenty-four items with adequate consistency and validity indices. Discussion and conclusion. The PPI is therefore a potentially useful psychometric measure for evaluating parenting practices among this type of population and could have major implications for the development of interventions and preventive programmes. It provides scientific bases for diagnostic decision-making and primary health care from the moment of initial contact to specialized medical care. [ABSTRACT FROM AUTHOR]

Introduction Obesity has a multifactorial etiology and is a global public health problem which also affects Mexican population. Obesity is characterized by excessive body adiposity, as well as high prevalence of diverse comorbidities, which diminish life quality. Sedentary lifestyle and hypercaloric food overconsumption are amongst the causes of obesity. It has been suggested that some traits seen in obese patients may represent an addictive behavior, similar to those observed in substance-dependent patients. Objective The aim of this work was the validation of the Spanish version of the Yale Food Addiction Rating Scale (YFAS) in a Mexican adult population sample. Method The scale was applied twice to 160 participants with a three weeks period in-between. The factorial model was corroborated with Bartlett's sphericity test and with that of Kaiser-Meyer-Olkin. Results Internal consistency was calculated by means of Cronbach's alpha which was a = 0.7963; reliability, measured with Spearman's coefficient by means of the test-retest method, was r = 0.565, n = 96. Convergence validity was estimated using the Binge Eating Scale (BES) and Spearman's correlation (r = 0.5868 p = 0.0001; n = 157). Bartlett's sphericity test showed (χ2 (300) = 1572.33, p < 0.05) and that of Kaiser-Meyer-Olkin (KMO = 0.825), showing consistency for the factorial model. Spearman's correlation between YFAS and body mass index (BMI) showed r = 0.2843 p = 0.001; n = 151. Discussion and conclusion The Spanish version of the YFAS showed psychometric properties not different from the original and adapted existing versions. Therefore, YFAS Spanish version could be useful in healthcare and clinical research in Mexican population. [ABSTRACT FROM AUTHOR]

Autism spectrum disorders (ASD) have demonstrated an increase in prevalence and are no longer considered a rare condition. The Autism Diagnostic Interview-Revised (ADI-R) and the Autism Diagnostic Observation Schedule-Generic (ADOS-G) have been gold standard instruments to diagnose ASD, but neither of these tools identifies associated comorbidity. The new Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Present and Life time version (K-SADS-PL-2009) added a supplement for assessing ASD. Objective The purpose of this study was to translate, adapt and analyze the interrater reliability of the KIDDIE SADS-PL-2009/ASD. Method The sample consisted of 40 children and adolescents, both male and female, with an age range between four and 17 years old, and presumptive ASD diagnosis. The original ASD screen and supplement interview was translated in to Spanish by two of the authors and retranslated by a certified translator blind to the study. Results Inter-rater reliability: Intraclass correlation coefficients varied from moderate to excellent for the following diagnosis both in the present and the past: Autism 0.79, 0.74; Asperger 0.85, 1.0; PDDNOS 0.72, 0.41. Kappa coefficients for expert evaluations in the present and the past were as following: Autism 0.89, 0.87; Asperger 0.77, 1.00; PDDNOS 0.69, 0.64. Diagnostic concordance between the initial clinical diagnosis and the following diagnosis through the interview was: 37.5%, with a 67.5% error margin. Conclusions In this study, the K-SADS-PL-2009/ASD showed moderate inter-rater reliability indicating that it can be used for clinical or research purposes in Mexican children and adolescents. [ABSTRACT FROM AUTHOR]

Several countries have noticed not only the adoption of body change strategies by males, but these may respond to different purposes: weight loss, weight gain and increased muscle tone or muscle mass. Nevertheless, instruments that allow the assessment of these aspects in a differentially way are scanty. Therefore, the aim of the present study was to obtain the Spanish version of the Body Modification Scale (BMS), as well as to examine its psychometric properties in adolescent men. The first study included the translation, adjustment and piloting of the BMS; internal consistency and factor structure were evaluated with 270 adolescents (Mage= 12.84); 171 of them participated in retest. The second study was conducted to prove, in an independent sample (n=200; Mage= l3.46), the adequacy of the factor structure derived from the original. The Spanish version of the BMS indicated to have adequate internal consistency (α=.88) and test-retest reliability (r=.80). The exploratory factor analysis derived initially four factors, showing conceptual overlap between two of them; therefore, it was opted to replicate the analysis performing an extraction to three factors. These explained 44.1% of the variance, grouping 20 of the 24 original items. The loss weight and increased muscle tone or muscle mass factors showed adequate reliability (α>.86; r>.80), resulting substantially lower the weight gain factor (.63 and .74, respectively). The confirmatory factor analysis supported the adequacy of both structures; however, the model here proposed showed a better fit. In general, the Spanish version of the BMS showed adequate psychometric properties in adolescent men. Nevertheless, this should be corroborated not only in other ages, but also in women. [ABSTRACT FROM AUTHOR]

Introduction Familiar satisfaction results from the continuous interplay of verbal and/or physical interactions between subjects and the other members of their family. This satisfaction maintain relations to the coherence, fairness, fun, support, lack of conflicts, affective proximity, confidence, cohesion, adaptation, allocation and acceptance of roles and tasks, open communication and the acceptance in general of the own family. The use of developed psychological tests constructed in other countries is a frequent practice in the world. The validation and standardization of the test imply to establish measurement rules and scales of qualification for a determined population, when it is different from the original population in which it was created or where the instrument is used habitually. The objective of this study was to collect the normative data of the Family Satisfaction by Adjectives Scale (FSAS) in children and adolescents of Mexico City. Material and methods A cross-sectional study was performed in 476 men and women; 8 to 15 years 11 months of age. The survey family satisfaction by adjectives scale (FSAS) by Barraca and López-Yarto was applied. The data were analyzed with the Statistical Package for Social Sciences (SPSS v. 17). Results The sample was conformed by 226 men (47.5%) and 250 women (52.5%). Of these, 237 were children (8 to 11 years and 11 months of age) and 239 were adolescents (12 to 15 years and 11 months of age). It was found that Family Satisfaction by Adjectives Scale (FSAS) has very good reliability (α=.89), construct (50% total variance), content and discriminative validity among children and adolescents (p.000). [ABSTRACT FROM AUTHOR]

Excessive daytime sleepiness (EDS) is a highly disabling sleep disorder related to alterations in behavioral performance, work injuries and vehicle accidents. A high prevalence of EDS (from 16% to 32%) in the general population has been reported. The Functional Outcomes Sleep Questionnaire (FOSQ) is an instrument that measures the impact of EDS in a patient's functional state in different sleep disorders. This questionnaire has been validated in different countries (Norway, Turkey, Spain). Therefore, the objective of this study was to obtain the cultural validation, the internal consistency, construct validity and factor congruence of the adapted questionnaire for the inhabitants of Mexico City (FOSQ-México). In the first part of the study we translated the questionnaire using the standard methodological process. The FOSQ cultural adaptation was made by the Natural Modified Semantic Networks technique in a sample of 78 participants. In the second part, the adapted FOSQ was applied to 152 participants to test items discrimination, internal consistency, factor analysis by principal-components and factorial congruence with the original version. The principal-components analysis of the FOSQ yielded six meaningful factors that explained 67.2% of the total variance, an average a coefficient between 0.85 to 0.94 for the six factors. The factorial congruence coefficients ranged from 0.360 to 0.969 between the original and the FOSQ-México version. This study demonstrated that the FOSQ version for inhabitants of Mexico City is reliable, valid and conceptually equivalent to the American version. [ABSTRACT FROM AUTHOR]

Smoker's craving is one of the most important problems in tobacco cessation treatment. The aim of this study was to elaborate a self report questionnaire to assess smoking urge. Development process was carried out in two parts: construction of items using a natural modified semantic networks method. It was administered to 42 smokers; after that, the first version of the questionnaire was answered by 222 smokers. Internal consistency was obtained and an analysis of discrimination was conducted on the items; then, a factorial analysis with varimax rotation using principal components method was carried out, resulting in 12 items on three factors that explain 76% of the variance and 0.92 Chronbach's alpha. [ABSTRACT FROM AUTHOR]

Depression is a mental health condition with a high prevalence in the population, low rates of detection in the health system, and a significant influence in the quality of life of individuals, affecting their family and social contexts. Because of this, research focusing on the development of instruments to measure depression has been an active area of research with a growing development in the Latin American context. In this paper, we present a brief version of the Center for Epidemiological Studies-Depression Scale (CESD-20), and analyze its psychometric properties, factorial structure, and construct validity in a sample of Spanish adult population. Our aim is to provide researchers and professionals of Spanish-speaking countries with an instrument that allows to obtain relevant information about the mental health of individuals in a reliable and efficient way. The CESD-20 was originally designed to evaluate the severity of depressive symptomatology in adult population and has shown excellent properties among both adult and adolescent populations. The CESD evaluates depressed mood, positive affect, somatic and retarded activity and negative perception of interpersonal relationships during the last week. There is extensive literature about the factorial structure of the original instrument. In this sense, there is a general agreement among researches about the usefulness of using a summed up score of the 20 items to reflect depressive symptomatology. This global score is used as an indicator of the individual risk of developing clinic depression rather than to classify depressed individuals. The Spanish version of the original CESD-20 has been consistently validated in different populations, but so far a brief version in this language has not been avaliable to researchers. In this study we explore the internal consistency and factorial structure of a 7-item version (CESD-7), as well as its construct validity. To analyze the construct validity of the CESD-7 we explore the relationships of the scale scores with two variables of the physiological and social context, respectively. On the one hand, we explore the relationship between health perceptions and both the original and brief versions of the CESD. On the other hand, we analyze the relationship between social integration and the two versions of the CESD. There is extensive empirical evidence about the relationship of depression with physical health and social integration. In this sense, there is a general agreement as to the association between poor health conditions and higher levels of depression over time. Likewise, the levels of social integration have been traditionally regarded as antecedents of depression. Therefore, we expect that both the original and brief versions of the CESD would be negatively associated with physical health and social integration. Moreover, the statistical relationships among these constructs would not be different when analyzed with the original or brief versions of the CESD. This would indicate that the brief version might be used as a substitute of the long one. Method Participants For this study we used data from a two-wave panel design with repeated measures in a community sample of Spanish adult population. In the first panel, 1051 participants of both sexes with ages ranging from 18 to 80 years completed the questionnaires. Participants in this panel were selected from a cross-section of representative neighbourhoods from a one million metropolitan area (Valencia, Spain). Participants completed questionnaires refering to their mental health, physical health, and social integration. Age, sex, educational level, and household income of participants were also coded. After six months, almost 75% (N = 740) of the respondents completed the same questionnaires in the second panel. Attrition analyses between respondents and drop-outs showed nonsignificant differences in socio-demographic variables.… [ABSTRACT FROM AUTHOR]

Introduction Childrearing or parenting is the assumption of responsibility for the emotional, social and physical growth and development of a child. Research literature has identified three related components commonly associated to rearing or parenting: a) spontaneous emotions and attitudes that are non-goal directed parental behaviors such as gestures, changes in the tone of voice, temperamental bursts, body language; b) specific goal-directed parental practices, which are better understood in the context of a socialization domain (academic achievement, peer cooperation), and c) the value system and beliefs of parents related to socialization goals of their children. Based on sound empirical data, there is no doubt about the impact of child-rearing environments on a wide variety of outcomes, ranging from normal variations of adaptive functioning and school success to an array of psychopathological results such as drug abuse, aggressive behavior, and anxiety in children and adolescents. During adolescence, parenting implies the transformation of the relationships between parents and children. This is a critical transition period in which the emerging social demands turn it into a particularly vulnerable period of life. Psychological distress that arises in adolescents may threaten their mental health on a medium and long term-basis. Based on an exhaustive literature study related to the parent-child relationship and the shared family environment, Repetti et al. suggest that conflict, lack of cohesion and organization, as well as unsupportive, cold and neglectful environments, were characteristic of families in risk of developing physical and mental problems. Adolescent studies provided evidence related to alcohol and drugs abuse, involvement in pregnancy, aggressive behaviour and delinquency as outcomes for children from families lacking cohesion and orderliness, as well as emotional warmth, support and involvement in parenting. Thus, it is important to rely on instruments that measure parenting and whose dimensions have proven to be relevant to the outcomes evaluated. One empirically evaluated instrument, in terms of internal consistency, construct validity, and convergent and divergent validity in transcultural context, is the Egna Minnen Betraffande Uppfostran-My memories of upbringing (EMBU). It has been extensively used and adapted in more than 25 countries, including Spanish-speaking populations from Guatemala, Venezuela and Spain. Factor analyses have revealed four factors (emotional warmth, rejection, control/overprotection and favouring subject), and multiple studies have documented the validity, reliability and cross-national transferability of the EMBU. Criticism regarding the retrospective nature of the EMBU has been overcome by designs with younger samples confirming its cross-stability for all scales except favouritism scale. There is a lack of instruments measuring parenting in Spanish-speaking countries. It is imperative to evaluate parental perceptions with adolescents as the source of information. There is, therefore, a need to empirically evaluate a reliable and valid parenting measurement, whose relational nature dimensions (warmth/rejection, control) can also be compared with those found in other countries. The purpose of the present study was to explore the psychometric properties of the EMBU-I in a sample of Mexican adolescents. In particular, its aim was to test the reliability (internal consistency), the congruency of the dimensions for fathers and mothers and within the scales comprising the EMBU, and its convergent and divergent validity. Method Seven hundred seventy five adolescents, with a mean age of 13.81 years, from two secondary schools, one public and one private, participated in the study. Instruments EMBU-C, parental involvement in studies scale, and the cohesion, conflict and organization scales from the FES.… [ABSTRACT FROM AUTHOR]

Background Psychopathology in children can be conceptualized as a normal development that has gone awry. That is, some conducts which are expectable at a certain age could turn to be inappropriate and pathological if they persist. When some traits, conducts or signs are very conspicuous and they are frequently present together, they are conventionally called syndromes. Studies registering children's observed conducts by the parents have been very useful to identify groups of symptoms, and several scales have been designed to elicit psychopathology such as the Children's Behavior Questionnaire (CBQ), Conner's scales, and the Child Behavior Checklist, CBCL-P. With the exception of the CBQ, the other two instruments, although frequently used as screening instruments in several studies, are too long or too specific to be systematically employed at the general practice services and in the community. More recently, Goodman designed the Strengths and Difficulties Questionnaire (SDQ), which is a 25-item instrument showing an acceptable predictive validity for three groups of disorders: conduct, emotional, hyperactivity and inattentive. In Mexico, our epidemiological work on children's mental health started at the end of the eighties using the Report Questionnaire for Children (RQC) which is a 10-item screening instrument developed at the end of the seventies for a WHO collaborative research with the aim of extending psychiatric services to primary care settings. In our population, the instrument showed good efficiency with a positive predictive value (PPV) of 76% and a negative predictive value (NPV) of 99%, and it has been useful in detecting mental health problems both in the general population, as well as in primary care services. However, the need to identify what kind of disorders are they and estimating their prevalence remains. The Brief Screening and Diagnostic Questionnaire (CBTD) was built based on previous experience using the RQC. Seventeen items which explored symptoms frequently reported as motives for seeking attention at the out-patient mental health services were added to the original 10 questions of the RQC. Most of them are items included in the CBCL-P, which explore hyperactivity, impulsivity, attention deficit, sadness, inhibition, oppositional and antisocial behaviors, and eating behaviors associated with low or high weight. The aim was to include cardinal symptoms that could lead to identify probable specific syndromes and disorders, based on the parent's report. The reliability of the instrument was measured using the Kuder-Richarson coefficient (KR-20), obtaining a 0.81 value. Based on responses obtained in a general population sample of 1686 children aged 4 to 16 years in Mexico City, the score at the 90th percentile, five symptoms, was established to define probable caseness. Also, using logistic regression analysis, the association between the cardinal symptoms for different disorders -as defined in the DSMIV and ICD-10 diagnostic criteria- and the rest of the items from the questionnaire was studied in order to obtain symptom profiles or syndromes signaling probable psychiatric disorders. The main objective of the present study was to evaluate the concurrent validity and the efficiency of the diagnostic algorithms of the CBTD, as compared with the psychiatric diagnoses of children attended at two out-patient mental health services in Mexico City. Method A random sample of consecutive new out-patients aged 4 to 16 years was obtained. The CBTD was administered to the accompanying parent before the consultation. Clinical evaluation was done independently and blind to these results; the psychiatrists emitted diagnoses following the ICD-10 criteria.… [ABSTRACT FROM AUTHOR]

Empathy may vary among individuals depending on social, educational, and personal experiences, and it corresponds to an interpersonal ability and a clinical competence component. Hence, the availability of a valid and reliable instrument for measuring empathy among medical doctors is a critical issue. However, the instrument should be culturally adapted for the population of interest. Therefore, the present study was designed for evaluating the validity and reliability of the Spanish version of the JPES among Mexican medical students. [ABSTRACT FROM AUTHOR]

Women are especially vulnerable to anxiety and depressive disorders, as shown in the international literature and, in our country, in the National Survey of Psychiatric Epidemiology. However, it is important not only to identify the disorders as such, but also to identify the symptoms, that though not becoming a disorder generate illnesses in women and can respond to psychopharmacological or psychotherapeutic interventions. The Symptom Check List (SCL 90) is a widely used instrument. In this study, three groups of women were assessed: one group of the community (as reference group), a second one, of women diagnosed as depressed in a third level psychiatric institution, and another group of women with a temporomandibular disorder (TMD). The main objective of this study was to identify the psychometric characteristics of the SCL-90. [ABSTRACT FROM AUTHOR]

A genetic epidemiology paradigm employed in the identification of genes associated with a disease depends on the comparison of the frequency of common genetic variants between groups of individuals who possess a relevant trait versus those who do not show the trait (i.e., cases vs. controls genetic association study). The adequate classification of groups of contrast is therefore of seminal importance for the identification of relevant genes. For psychiatric disorders, the careful clinical evaluation of particular symptoms is the basis for the classification of the "affected or disease group". However, in many psychiatric genetics studies the constitution of the "control" or "normal" group has been based only on the absence of an overt expression of symptoms, where no particular emphasis is given to the symptom evaluation to exclude the phenotype. The use of psychometric instruments can help to assess some behavioral traits of clinical relevance. In turn, these assessments could help in the diagnosis, prognosis and treatment of disorders. Moreover, quantitative assessments let determine if these traits belong to the normal range of variation in a population or could be a deviation of the trend. The Symptom Checklist 90 (SCL90) is a 90-item self-report inventory that assesses the level of distress recently experienced by the subject. It is comprised of nine dimensions: somatization, obsessive-compulsive, interpersonal sensitivity, depression, anxiety, hostility, phobic anxiety, paranoid ideation, psychoticism and a General Severity Index (GSI). Although the SCL 90 is a well-accepted and widely used instrument in research and clinical practice in many countries, we found a scarcity of relevant studies for Latin America and a lack of normative data for Mexican populations. The aim of the present report was to evaluate the reliability and construct validity of the SCL 90. [ABSTRACT FROM AUTHOR]