Implementing a challenge-based learning experience in a bioinstrumentation blended course.

BACKGROUND: Bioinstrumentation is essential to biomedical engineering (BME) undergraduate education and professional practice. Several strategies have been suggested to provide BME students with hands-on experiences throughout the curriculum, promoting their preparedness to pursue careers in industry and academia while increasing their learning and engagement. This paper describes the implementation of challenge-based learning (CBL) in an undergraduate bioinstrumentation blended course over the COVID-19 pandemic. METHODS: The CBL experience was implemented in a third-year bioinstrumentation course from the BME program at Tecnologico de Monterrey. Thirty-nine students enrolled in two sections formed fourteen teams that tackled blended learning activities, including online communication, lab experiments, and in-person CBL activities. Regarding the latter, students were challenged to design, prototype, and test a respiratory or cardiac gating device for radiotherapy. An institutional student opinion survey was used to assess the success of our CBL implementation. RESULTS: Student responses to the end-of-term survey showed that they strongly agreed that this course challenged them to learn new concepts and develop new skills. Furthermore, they rated the student-lecturer interaction very positively despite the blended format. Overall, students assessed their learning experience positively. However, implementing this CBL experience required a substantial time increase in planning, student tutoring, and constant communication between lecturers and the industry partner. CONCLUSION: This work provides an effective instance of CBL for BME education to improve students' learning experience despite decreased resource efficiency. Our claim is supported by the student's performance and the positive feedback from our industrial partner.

Transdisciplinary experiential learning in biomedical engineering education for healthcare systems improvement.

BACKGROUND: The growing demand for more efficient, timely, and safer health services, together with insufficient resources, put unprecedented pressure on health systems worldwide. This challenge has motivated the application of principles and tools of operations management and lean systems to healthcare processes to maximize value while reducing waste. Consequently, there is an increasing need for professionals with the appropriate clinical experience and skills in systems and process engineering. Given their multidisciplinary education and training, biomedical engineering professionals are likely among the most suitable to assume this role. In this context, biomedical engineering education must prepare students for a transdisciplinary professional role by including concepts, methods, and tools that commonly belong to industrial engineering. This work aims to create relevant learning experiences for biomedical engineering education to expand transdisciplinary knowledge and skills in students to improve and optimize hospital and healthcare care processes. METHODS: Healthcare processes were translated into specific learning experiences using the Analysis, Design, Development, Implementation, and Evaluation (ADDIE) model. This model allowed us to systematically identify the context where learning experiences were expected to occur, the new concepts and skills to be developed through these experiences, the stages of the student's learning journey, the resources required to implement the learning experiences, and the assessment and evaluation methods. The learning journey was structured around Kolb's experiential learning cycle, which considers four stages: concrete experience, reflective observation, abstract conceptualization, and active experimentation. Data on the student's learning and experience were collected through formative and summative assessments and a student opinion survey. RESULTS: The proposed learning experiences were implemented in a 16-week elective course on hospital management for last-year biomedical engineering undergraduate students. Students engaged in analyzing and redesigning healthcare operations for improvement and optimization. Namely, students observed a relevant healthcare process, identified a problem, and defined an improvement and deployment plan. These activities were carried out using tools drawn from industrial engineering, which expanded their traditional professional role. The fieldwork occurred in two large hospitals and a university medical service in Mexico. A transdisciplinary teaching team designed and implemented these learning experiences. CONCLUSIONS: This teaching-learning experience benefited students and faculty concerning public participation, transdisciplinarity, and situated learning. However, the time devoted to the proposed learning experience represented a challenge.

On the use of approximate entropy and sample entropy with centre of pressure time-series.

BACKGROUND: Approximate entropy (ApEn) and sample entropy (SampEn) have been previously used to quantify the regularity in centre of pressure (COP) time-series in different experimental groups and/or conditions. ApEn and SampEn are very sensitive to their input parameters: m (subseries length), r (tolerance) and N (data length). Yet, the effects of changing those parameters have been scarcely investigated in the analysis of COP time-series. This study aimed to investigate the effects of changing parameters m, r and N on ApEn and SampEn values in COP time-series, as well as the ability of these entropy measures to discriminate between groups. METHODS: A public dataset of COP time-series was used. ApEn and SampEn were calculated for m = {2, 3, 4, 5}, r = {0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5} and N = {600, 1200} (30 and 60 s, respectively). Subjects were stratified in young adults (age < 60, n = 85), and older adults (age ≥ 60) with (n = 18) and without (n = 56) falls in the last year. The effects of changing parameters m, r and N on ApEn and SampEn were investigated with a three-way ANOVA. The ability of ApEn and SampEn to discriminate between groups was investigated with a mixed ANOVA (within-subject factors: m, r and N; between-subject factor: group). Specific combinations of m, r and N producing significant differences between groups were identified using the Tukey's honest significant difference procedure. RESULTS: A significant three-way interaction between m, r and N confirmed the sensitivity of ApEn and SampEn to the input parameters. SampEn showed a higher consistency and ability to discriminate between groups than ApEn. Significant differences between groups were mostly observed in longer (N = 1200) COP time-series in the anterior-posterior direction. Those differences were observed for specific combinations of m and r, highlighting the importance of an adequate selection of input parameters. CONCLUSIONS: Future studies should favour SampEn over ApEn and longer time-series (≥ 60 s) over shorter ones (e.g. 30 s). The use of parameter combinations such as SampEn (m = {4, 5}, r = {0.25, 0.3, 0.35}) is recommended.

Developing a virtual reality and AI-based framework for advanced digital manufacturing and nearshoring opportunities in Mexico.

The growing expansion of the manufacturing sector, particularly in Mexico, has revealed a spectrum of nearshoring opportunities yet is paralleled by a discernible void in educational tools for various stakeholders, such as engineers, students, and decision-makers. This paper introduces a state-of-the-art framework, incorporating virtual reality (VR) and artificial intelligence (AI) to metamorphose the pedagogy of advanced manufacturing systems. Through a case study focused on the design, production, and evaluation of a robotic platform, the framework endeavors to offer an exhaustive educational experience via an interactive VR environment, encapsulating (1) Robotic platform system design and modeling, enabling users to immerse themselves in the design and simulation of robotic platforms under varied conditions; (2) Virtual manufacturing company, presenting a detailed virtual manufacturing setup to enhance users' comprehension of manufacturing processes and systems, and problem-solving in realistic settings; and (3) Product evaluation, wherein users employ VR to meticulously assess the robotic platform, ensuring optimal functionality and customer satisfaction. This innovative framework melds theoretical acumen with practical application in advanced manufacturing, preparing entities to navigate Mexico's manufacturing sector's vibrant and competitive nearshoring landscape. It creates an immersive environment for understanding modern manufacturing challenges, fostering Mexico's manufacturing sector growth, and maximizing nearshoring opportunities for stakeholders.

Optical Marker-Based Motion Capture of the Human Spine: A Scoping Review of Study Design and Outcomes.

Biomechanical analysis of the human spine is crucial to understanding injury patterns. Motion capture technology has gained attention due to its non-invasive nature. Nevertheless, traditional motion capture studies consider the spine a single rigid segment, although its alignment changes during movement. Moreover, guidelines that indicate where markers should be placed for a specific exercise do not exist. This study aims to review the methods used to assess spine biomechanics using motion capture systems to determine the marker sets used, the protocols used, the resulting parameters, the analysed activities, and the characteristics of the studied populations. PRISMA guidelines were used to perform a Scoping Review using SCOPUS and Web of Science databases. Fifty-six journal and conference articles from 1997 to 2023 were considered for the analysis. This review showed that Plug-in-Gait is the most used marker set. The lumbar spine is the segment that generates the most interest because of its high mobility and function as a weight supporter. Furthermore, angular position and velocity are the most common outcomes when studying the spine. Walking, standing, and range of movement were the most studied activities compared to sports and work-related activities. Male and female participants were recruited similarly across all included articles. This review presents the motion capture techniques and measurement outcomes of biomechanical studies of the human spine, to help standardize the field. This work also discusses trends in marker sets, study outcomes, studied segments and segmentation approaches.

Recurrence quantification analysis of center of pressure trajectories for balance and fall-risk assessment in young and older adults.

The prevalence and impact of balance impairments and falls in older adults have motivated several studies on the characterization of human balance. This study aimed to determine the ability of recurrence quantification analysis (RQA) measures to characterize balance control during quiet standing in young and older adults and to discriminate between different fall risk groups. We analyze center pressure trajectories in the medial-lateral and anterior-posterior directions from a publicly available static posturography dataset that contains tests acquired under four vision-surface testing conditions. Participants were retrospectively classified as young adults (age<60, n=85), non-fallers (age≥60, falls=0, n=56), and fallers (age≥60, falls≥1, n=18). Mixed ANOVA and post hoc analyzes were performed to test for differences between groups. For CoP fluctuations in the anterior-posterior direction, all RQA measures showed significantly higher values for young than older adults when standing on a compliant surface, indicating less predictable and stable balance control among seniors under testing conditions where sensory information is restricted or altered. However, no significant differences between non-fallers and fallers were observed. These results support the use of RQA to characterize balance control in young and old adults, but not to discriminate between different fall risk groups.

A machine learning approach for hypertension detection based on photoplethysmography and clinical data.

High blood pressure early screening remains a challenge due to the lack of symptoms associated with it. Accordingly, noninvasive methods based on photoplethysmography (PPG) or clinical data analysis and the training of machine learning techniques for hypertension detection have been proposed in the literature. Nevertheless, several challenges arise when analyzing PPG signals, such as the need for high-quality signals for morphological feature extraction from PPG related to high blood pressure. On the other hand, another popular approach is to use deep learning techniques to avoid the feature extraction process. Nonetheless, this method requires high computational power and behaves as a black-box approach, which impedes application in a medical context. In addition, considering only the socio-demographic and clinical data of the subject does not allow constant monitoring. This work proposes to use the wavelet scattering transform as a feature extraction technique to obtain features from PPG data and combine it with clinical data to detect early hypertension stages by applying Early and Late Fusion. This analysis showed that the PPG features derived from the wavelet scattering transform combined with a support vector machine can classify normotension and prehypertension with an accuracy of 71.42% and an F1-score of 76%. However, classifying normotension and prehypertension by considering both the features extracted from PPG signals through wavelet scattering transform and clinical variables such as age, body mass index, and heart rate by either Late Fusion or Early Fusion did not provide better performance than considering each data type separately in terms of accuracy and F1-score.

Machine learning and deep learning predictive models for type 2 diabetes: a systematic review.

Diabetes Mellitus is a severe, chronic disease that occurs when blood glucose levels rise above certain limits. Over the last years, machine and deep learning techniques have been used to predict diabetes and its complications. However, researchers and developers still face two main challenges when building type 2 diabetes predictive models. First, there is considerable heterogeneity in previous studies regarding techniques used, making it challenging to identify the optimal one. Second, there is a lack of transparency about the features used in the models, which reduces their interpretability. This systematic review aimed at providing answers to the above challenges. The review followed the PRISMA methodology primarily, enriched with the one proposed by Keele and Durham Universities. Ninety studies were included, and the type of model, complementary techniques, dataset, and performance parameters reported were extracted. Eighteen different types of models were compared, with tree-based algorithms showing top performances. Deep Neural Networks proved suboptimal, despite their ability to deal with big and dirty data. Balancing data and feature selection techniques proved helpful to increase the model's efficiency. Models trained on tidy datasets achieved almost perfect models.

Wearable Inertial Sensors for Fall Risk Assessment and Prediction in Older Adults: A Systematic Review and Meta-Analysis.

Wearable inertial sensors have been widely investigated for fall risk assessment and prediction in older adults. However, heterogeneity in published studies in terms of sensor location, task assessed and features extracted is high, making challenging evidence-based design of new studies and/or real-life applications. We conducted a systematic review and meta-analysis to appraise the best available evidence in the field. Namely, we applied established statistical methods for the analysis of categorical data to identify optimal combinations of sensor locations, tasks, and feature categories. We also conducted a meta-analysis on sensor-based features to identify a set of significant features and their pivot values. The results demonstrated that with a walking test, the most effective feature to assess the risk of falling was the velocity with the sensor placed on the shins. Conversely, during quite standing, linear acceleration measured at the lower back was the most effective combination of feature-placement. Similarly, during the sit-to-stand and/or the stand-to-sit tests, linear acceleration measured at the lower back seems to be the most effective feature-placement combination. The meta-analysis demonstrated that four features resulted significantly higher in fallers: the root-mean-square acceleration in the mediolateral direction during quiet standing with eyes closed [Mean Difference (MD): 0.01 g; 95% Confidence Interval (CI95%): 0.006 to 0.014]; the number of steps (MD: 1.638 steps; CI95%: 0.384 to 2.892) and total time (MD: 2.274 seconds; CI95%: 0.531 to 4.017) to complete the timed up and go test; and the step time (MD: 0.053; CI95%: 0.012 to 0.095; p = 0.01) during walking.

Day-to-day variations in sleep quality affect standing balance in healthy adults.

Acute sleep deprivation is known to affect human balance and posture control. However, the effects of variations in sleep quality and pattern over consecutive days have received less attention. This study investigated the associations between day-to-day variations in sleep quality and standing balance in healthy subjects. Twenty volunteers (12 females and 8 males; age: 28.8 ± 5.7 years, body mass index: 23.4 ± 3.4 kg/m2, resting heart rate: 63.1 ± 8.7 bpm) with no history of sleep disorders or balance impairments participated in the study. Sleep and balance were assessed over two consecutive days. Sleep quality variations were assessed using sleep diary, actigraphy and heart rate variability (HRV) measures. Sleep was monitored at home, using an unobtrusive wearable device. Balance was assessed in a gait lab using foot centre of pressure (COP) displacement during quiet standing. Subjects with a day-to-day deterioration in sleep quantity and quality (i.e., decreased duration and increased fragmentation, increased nocturnal activity and decreased HRV) exhibited significant changes in balance (i.e., larger COP area, amplitude and standard deviation). Conversely, subjects with no significant alterations in sleep quantity and quality showed no significant changes in COP displacements. These results confirmed our hypothesis that changes in sleep quality and pattern over consecutive days may affect balance.

Are ultra-short heart rate variability features good surrogates of short-term ones? State-of-the-art review and recommendations.

Ultra-short heart rate variability (HRV) analysis refers to the study of HRV features in excerpts of length <5 min. Ultra-short HRV is widely growing in many healthcare applications for monitoring individual's health and well-being status, especially in combination with wearable sensors, mobile phones, and smart-watches. Long-term (nominally 24 h) and short-term (nominally 5 min) HRV features have been widely investigated, physiologically justified and clear guidelines for analysing HRV in 5 min or 24 h are available. Conversely, the reliability of ultra-short HRV features remains unclear and many investigations have adopted ultra-short HRV analysis without questioning its validity. This is partially due to the lack of accepted algorithms guiding investigators to systematically assess ultra-short HRV reliability. This Letter critically reviewed the existing literature, aiming to identify the most suitable algorithms, and harmonise them to suggest a standard protocol that scholars may use as a reference in future studies. The results of the literature review were surprising, because, among the 29 reviewed papers, only one paper used a rigorous method, whereas the others employed methods that were partially or completely unreliable due to the incorrect use of statistical tests. This Letter provides recommendations on how to assess ultra-short HRV features reliably and proposes an inclusive algorithm that summarises the state-of-the-art knowledge in this area.

The contribution of the therapist's competence in the treatment of adolescents with generalized social phobia.

BACKGROUND: The purpose of this study was to explore which of the outcomes attained by the application of the psychological program Intervención en Adolescentes con Fobia Social (Intervention in Adolescents with Social Phobia) can be attributed to the therapist's competence. METHOD: The experimental study consists of three conditions: Waiting list control, Group treated by expert psychologists, and Group treated by inexperienced psychologists, with a sample of 110 Spanish adolescents whose mean age was 15.42 years (SD = 0.97, range: 14-18). All participants met the criteria for diagnosis of Generalized Social Phobia) and most of them were female (65.45%). RESULTS: (i) The effect size attributable to the therapist was low compared to the effect size associated with the manual-based treatment program in the dependent variables measured, and (ii) Expert therapists attained a much greater remission of the criteria for the diagnosis of Generalized Social Phobia among participants than did the inexperienced therapists. CONCLUSIONS: The IAFS Program was responsible for most of the change measured in participants.

Community versus clinical cognitive-behavioral intervention in young-adult Spanish population with generalized social phobia / Intervención cognitivo-conductual comunitaria versus intervención clínica en jóvenes adultos españoles con fobia social generalizada

Ei objetivo del estudio es mejorar los resultados informados por las revisiones sobre el tratamiento de adultos con Fobia social generalizada. La muestra la integraron 91 participantes con Fobia social generalizada (EM: 19.90 años; DT: 1.05) asignados aleatoriamente a tres condiciones experimentales, evaluados antes y después del tratamiento, y a los 6, 12, y 24 meses en los grupos tratados. Los resultados muestran (a) la efectividad de la detección en el contexto comunitario versus la intervención clínica, en el corto y medio plazo, y (b) una mejora significativa de los efectos del tratamiento, frente a los de las revisiones de las intervenciones clínicas ad hoc, tanto en los abandonos como en las tasas de recuperación. Ello permite concluir que esta modalidad de aplicación del tratamiento cognitivo-conductual puede ser una estrategia complementaria a la convencional con la que mejorar los resultados actuales de la intervención psicológica en este trastorno.

The study investigates how to improve the results reported by the reviews on the effects of clinical interventions in adults with Generalized social phobia. The sample was composed of 91 participants (median age = 19.90 years, SD = 1.05) randomly assigned to three experimental conditions. The evaluations were conducted before and after treatment in all three groups and at 6-, 12-, and 24-month follow-up for the treatment groups. The results show (a) the effectiveness of the cognitive-behavioral strategy of detection and intervention, in a community context, versus clinical intervention both for the short and medium term; and (b) a significant improvement over the percentages of dropouts and of rates of complete recovery from the disorder. These findings allow us to conclude that the cognitive-behavioral strategy of detection and intervention, in a community context is shown to be a complementary intervention to the conventional and with high efficiency ratios.

Efectos del terapeuta en el tratamiento de adolescentes con fobia social generalizada / Therapist Effects in the Treatment of Adolescents with Generalized Social Phobia

El propósito de este estudio es verificar la parte de los resultados del Programa para la Intervención en Adolescentes con Fobia Social que pueden ser atribuidos al grado experto del terapeuta. Se presentan los resultados obtenidos en tres condiciones experimentales (grupos experto, cuasi-experto e inexperto), integradas por 46 adolescentes españoles con una edad media de 15.37 años (DT: 1.04; rango: 14-18), siendo la mayoría chicas (67.4%) que cursaban 4º de E.S.O (46.70%). Todos cumplieron los criterios requeridos para el diagnóstico de Fobia Social Generalizada (APA, 2000). Los resultados muestran que (I) el tamaño del efecto que se puede atribuir a los terapeutas es bajo, (II) que la magnitud del tamaño del efecto obtenido correlaciona con la magnitud del grado experto en las variables más sensibles al cambio terapéutico, (III) que tales resultados no alcanzan diferencias con significación estadística entre las tres condiciones experimentales

The purpose of this study is to verify which part of the results of the Intervention Program for Adolescents with Social Phobia can be attributed to the level of competence of the therapist. We present the results of three experimental conditions (expert, quasi-expert and inexperienced),including 46 Spanish adolescents with a mean age of 15.37 years (SD = 1.04, range: 14-18). Most of the participants were female (67.40%) and were in 4th grade of ESO (46.70%). All of them met the criteria for diagnosis of Generalized Social Phobia. The results showed that (I) the effect size that could be attributed to therapists was low, (II) the magnitude of the effect size obtained correlated with the magnitude of the expert level in the most sensitive variables to therapeutic change, and (III) these results did not reach statistically significant differences among the three experimental conditions. The data allow us to conclude that found to be relevant the impact of therapist competence on the results most of the variance in the results is directly related to the effect of manualized treatment program that has been implemented

The contribution of the therapist's competence in the treatment of adolescents with generalized social phobia / Contribución de la competencia del terapeuta en el tratamiento de adolescentes con fobia social generalizada

BACKGROUND: The purpose of this study was to explore which of the outcomes attained by the application of the psychological program Intervención en Adolescentes con Fobia Social (Intervention in Adolescents with Social Phobia) can be attributed to the therapist's competence. METHOD: The experimental study consists of three conditions: Waiting list control, Group treated by expert psychologists, and Group treated by inexperienced psychologists, with a sample of 110 Spanish adolescents whose mean age was 15.42 years (SD = 0.97, range: 14-18). All participants met the criteria for diagnosis of Generalized Social Phobia) and most of them were female (65.45%). RESULTS: (I) The effect size attributable to the therapist was low compared to the effect size associated with the manual-based treatment program in the dependent variables measured, and (II) Expert therapists attained a much greater remission of the criteria for the diagnosis of Generalized Social Phobia among participants than did the inexperienced therapists. CONCLUSIONS: The IAFS Program was responsible for most of the change measured in participants

ANTECEDENTES: el propósito de este estudio fue verificar la parte de los efectos generados por la aplicación del Programa para la Intervención en Adolescentes con Fobia Social que pueden ser atribuidos a la competencia del terapeuta. MÉTODO: estudio experimental integrado por Grupo de control lista de espera, Grupo tratado por psicólogos expertos y Grupo tratado por psicólogos inexpertos. La muestra estuvo formada por 110 adolescentes españoles con una edad media de 15,42 años (DT: 0,97; rango: 14-18), siendo la mayoría chicas (65,45%). Todos cumplieron los criterios requeridos para el diagnóstico de Fobia Social Generalizada. RESULTADOS: (I) el Tamaño del efecto que se puede atribuir a los terapeutas es bajo frente a las magnitudes que alcanza el tamaño que se puede asociar con el Programa manualizado de tratamiento en las variables dependientes medidas, (II) los resultados obtenidos por los terapeutas expertos son mucho más relevantes que los de los inexpertos respecto de la remisión de los criterios requeridos para el diagnóstico de Fobia Social Generalizada. CONCLUSIONES: los efectos generados por el Programa de tratamiento son claramente superiores a los que pueden atribuirse a los terapeutas

The social phobia and anxiety inventory: first results of its reliability and structural validity in chilean adolescents / Inventario de ansiedad y fobia social: primeros resultados de fiabilidad y validez estructural en una muestra de adolescentes chilenos

En el presente estudio examinamos la fiabilidad y validez estructural de la versión chilena del ?Inventario de ansiedad y fobia social? (Social Phobia and Anxiety Inventary, SPAI; Turner, Beidel, Dancu y Stanley, 1989)), utilizando una muestra de 1040 adolescentes no clínicos (rango de edad entre 13 y 18 años). El análisis de validez estructural indicó la existencia de dos subescalas (Fobia Social y Agorafobia) claramente diferenciadas que explicaban un 43.4% de la varianza. Los índices de fiabilidad obtenidos fueron muy altos en cada una de las subescalas. A pesar de que se encontraron diferencias significativas debidas al sexo en ambas subescalas, los tamaños del efecto fueron muy bajos. Por otro lado, la variable edad resulta significativa en el subescala fobia social pero no en agorafobia, siendo igualmente la magnitud del efecto muy baja. Los resultados, en general, aportan evidencia empírica a favor de la fiabilidad y la validez de la versión chilena del Inventario de Ansiedad y Fobia Social.

In this report we examined the reliability and structural validity of the Chilean version of the Social Phobia and Anxiety Inventory, SPAI, (Turner, Beidel, Dancu y Stanley, 1989), using a sample of 1040 non clinical Chilean adolescents (range of age between 13 and 18 years). The structural validity analysis indicated the existence of two, clearly differentiated, subscales (Social Phobia and Agoraphobia) that explained 43.4% of the variance. The alpha reliability coefficients were very high in each one of the subscales. In spite of finding significant differences, for sex in both scales, the effect size was small. On the other hand, the age variable was significant in the social phobia scale but not in the agoraphobia one, but again the effect size was small. In general the results offer empirical evidence in support of the reliability and validity of the Chilean version of the Social Phobia and Anxiety Inventory.

Desafios para la Psicología de la salud en el ocaso del siglo XX / Challeges for the health psychology in the end of the XX century

Este artículo se centra en los desafíos que la Psicología de la Salud deberá enfrentar durante los próximos veinte a cincuenta años con miras a tener un impacto real en el campo de la salud. Aquellos desafíos provenientes desde el centro de la psicología misma se refieren a la necesidad de aumentar los estudios replicativos, a desarrollar comportamientos políticos en los futuros psicológicos y a trabajar más en el área de los procesos de toma de decisión a nivel macro social. Desde fuera de la psicología el primer desafió se refiere a la necesidad de globalizar la disciplina. Esta se ha centrado básicamente en estudios realizados en los Estados Unidos sin prestar mayor atención a la realidad a nivel mundial. En lo científico esto resulta una falta de validez externe y en lo profesional en una prácticamente nula representación de la disciplina en los organismos mundiales de salud. El segundo desafió proviene del uso de la llamada medicina alternativa o complementaria. Este hecho da la oportunidad de la Psicología de la Salud de utilizar su metodología para evaluar la bondad de estas intervenciones así como proponer constructor psicológicos que podrían explicar la efectividad de algunas de ellas: El último desafío externo proviene de los cambios demográficos; se espera que la expectativa de vida a nivel mundial alcance los 73 años y que las personas sobre 65 años alcanzaran a un diez por ciento de la población. Esto da la oportunidad de utilizar el conocimiento psicológico para asegurar una apropiada calidad de vida a ese segmento de la población, investigar más aspectos relacionados con el género y con la muerte.