Cataract surgery in cancer patients and its impact on quality of life as measured by the National Eye Institute Visual Functioning Questionnaire - 25 (NEI-VFQ-25)

Purpose. The measurement of quality of life has become an important topic in healthcare and in the allocation of limited healthcare resources. Improving the quality of life (QOL) in cancer patients is paramount. Cataract removal and lens implantation appears to improve patient well-being of cancer patients, though a formal measurement has never been published in the US literature. In this current study, National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25), a validated vision quality of life metric, was used to study the change in vision-related quality of life in cancer patients who underwent cataract extraction with intraocular lens implantation. ^ Methods. Under an IRB approved protocol, cancer patients who underwent cataract surgery with intraocular lens implantation (by a single surgeon) from December 2008 to March 2011, and who had completed a pre- and postoperative NEI-VFQ-25 were retrospectively reviewed. Post-operative data was collected at their routine 4-6 week post-op visit. Patients' demographics, cancer history, their pre and postoperative ocular examinations, visual acuities, and NEI-VFQ-25 with twelve components were included in the evaluation. The responses were evaluated using the Student t test, Spearman correlation and Wilcoxon signed rank test. ^ Results. 63 cases of cataract surgery (from 54 patients) from the MD Anderson Cancer Center were included in the study. Cancer patients had a significant improvement in the visual acuity (P<0.0001) postoperatively, along with a significant increase in vision-related quality of life (P<0.0001). Patients also had a statistically significant improvement in ten of the twelve subcategories which are addressed in the NEI-VFQ-25. ^ Conclusions. In our study, cataract extraction and intraocular implantation showed a significant impact on the vision-related quality of life in cancer patients. Although this study includes a small sample size, it serves as a positive pilot study to evaluate and quantify the impact of a surgical intervention on QOL in cancer patients and may help to design a larger study to measure vision related QOL per dollar spent for health care cost in cancer patients.^

Effect of patient accrual patterns on power and size of log-rank test for time-to-event outcome in clinical trials

The determination of size as well as power of a test is a vital part of a Clinical Trial Design. This research focuses on the simulation of clinical trial data with time-to-event as the primary outcome. It investigates the impact of different recruitment patterns, and time dependent hazard structures on size and power of the log-rank test. A non-homogeneous Poisson process is used to simulate entry times according to the different accrual patterns. A Weibull distribution is employed to simulate survival times according to the different hazard structures. The current study utilizes simulation methods to evaluate the effect of different recruitment patterns on size and power estimates of the log-rank test. The size of the log-rank test is estimated by simulating survival times with identical hazard rates between the treatment and the control arm of the study resulting in a hazard ratio of one. Powers of the log-rank test at specific values of hazard ratio (≠1) are estimated by simulating survival times with different, but proportional hazard rates for the two arms of the study. Different shapes (constant, decreasing, or increasing) of the hazard function of the Weibull distribution are also considered to assess the effect of hazard structure on the size and power of the log-rank test. ^

Impact of consciousness raising and social liberation on readiness to engage in regular physical activity among adults in Magnolia Park/Lawndale-Wayside, Houston, TX

According to the transtheoretical model, consciousness raising and social liberation are processes used to help individuals progress through the stages of change for a given behavior. This study assessed the impact of these two processes on readiness to engage in regular physical activity among a convenience sample of 35 adults in the Magnolia Park/Lawndale-Wayside area of Houston, TX. The duration of the study was approximately 4 weeks. All pre/post-test data were collected via self-administered surveys available in English or Spanish. Baseline data were used to determine the culturally relevant content of a one-dose intervention consisting of a presentation and dissemination of educational materials as well as a list of local physical activity opportunities. Although the intervention did not improve progression through the stages of change, significant increases were evident among 5 out of 6 processes of change. Based on these results and qualitative data, this study recommended that the Houston Parks and Recreation Department incorporate cultural competency into the design and publication of materials and revise the schedule of available programs (i.e.: increase the number of walking programs) in order to reflect the physical activity preferences of Magnolia Park/Lawndale-Wayside residents.^

THE IMPACT OF FAMILY HISTORY ON MEDULLARY THYROID CANCER IN MEN2A PATIENTS

The American Thyroid Association recently classified all MEN2A-associated codons into increasing risk levels A-C and stated that some patients may delay prophylactic thyroidectomy if certain criteria are met. One criterion is a less aggressive family history of MTC but whether families with the same mutated codon have variable MTC aggressiveness is not well described. We developed several novel measures of MTC aggressiveness and compared families with the same mutated codon to determine if there is significant inter-familial variability. Pedigrees of families with MEN2A were reviewed for codon mutated and proportion of RET mutation carriers with MTC. Individuals with MTC were classified as having local or distant MTC and whether they had progressive MTC. MTC status and age were assessed at diagnosis and most advanced MTC stage. For those without MTC, age was recorded at prophylactic thyroidectomy or last follow-up if the patient did not have a thyroidectomy. For each pedigree, the mean age of members without MTC, with MTC, and the proportion of RET mutation carriers with local or distant and progressive MTC were calculated. We assessed differences in these variables using ANOVA and the Fisher’s exact test. Sufficient data for analysis were available for families with mutated codons 609 (92 patients from 13 families), 618 (41 patients from 7 families), and 634 (152 patients from 13 families). The only significant differences found were the mean age of patients without MTC between families with codon 609 and 618 mutations even after accounting for prophylactic thyroidectomy (p=0.006 and 0.001, respectively), and in the mean age of MTC diagnosis between families with codon 618 and 634 mutations even after accounting for symptomatic presentation (p=0.023 and 0.014, respectively). However, these differences may be explained by generational differences in ascertainment of RET carriers and the availability of genetic testing when the proband initially presented.

The risk prediction for SPM and its impact on the survival in patients with head and neck squamous cell carcinoma

Head and Neck Squamous Cell Carcinoma (HNSCC) is the sixth common malignancy in the world, with high rates of developing second primary malignancy (SPM) and moderately low survival rates. This disease has become an enormous challenge in the cancer research and treatments. For HNSCC patients, a highly significant cause of post-treatment mortality and morbidity is the development of SPM. Hence, assessment of predicting the risk for the development of SPM would be very helpful for patients, clinicians and policy makers to estimate the survival of patients with HNSCC. In this study, we built a prognostic model to predict the risk of developing SPM in patients with newly diagnosed HNSCC. The dataset used in this research was obtained from The University of Texas MD Anderson Cancer Center. For the first aim, we used stepwise logistic regression to identify the prognostic factors for the development of SPM. Our final model contained cancer site and overall cancer stage as our risk factors for SPM. The Hosmer-Lemeshow test (p-value= 0.15>0.05) showed the final prognostic model fit the data well. The area under the ROC curve was 0.72 that suggested the discrimination ability of our model was acceptable. The internal validation confirmed the prognostic model was a good fit and the final prognostic model would not over optimistically predict the risk of SPM. This model needs external validation by using large data sample size before it can be generalized to predict SPM risk for other HNSCC patients. For the second aim, we utilized a multistate survival analysis approach to estimate the probability of death for HNSCC patients taking into consideration of the possibility of SPM. Patients without SPM were associated with longer survival. These findings suggest that the development of SPM could be a predictor of survival rates among the patients with HNSCC.^

Long-term impact of a weight management summer camp on obese children

Background: interventions that focus on improving eating habits, increasing physical activity, and reducing sedentary behaviors on weight status and body mass index percentile and z-scores in youths have not been well documented. This study aimed to determine the short and long term effects of a 2-week residential weight management summer camp program for youths on weight, BMI, BMI percentile, and BMI z-score. ^ Methods: A sample of 73 obese multiethnic 10-14 years old youths (11.9 ± 1.4) attended a weight management camp called Kamp K'aana for two weeks and completed a 12-month follow-up on height and weight. As part of Kamp K'aana, participants received a series of nutrition, physical activity and behavioral lessons and were on an 1800 kcal per day meal plan. Anthropometric measurements of height and weight were taken to calculate participants' BMI percentiles and z-scores. Paired t-tests, chi square test and ANCOVA, adjusting for age, gender, and ethnicity were used to assess changes in body weight, BMI, BMI percentiles and BMI z-scores pre to two-weeks post-camp and 12 months post-camp. ^ Results: Significant reductions in body weight of 3.6 ± 1.4 (P = 0.0000), BMI of 1.4 ± 0.54 (P = 0.0000), BMI percentile of 0.45 ± 0.06 (P = 0.0000), and BMI z-score of 0.1 ± 0.06 (P = 0.0000) were observed at the end of the camp. Significant reductions in BMI z-scores (P < 0.001) and BMI percentile (P < 0.001) were observed at the 12-month reunion when compared to pre- and two-weeks post camp data. There was a significant increase in weight and BMI (P = 0.0000) at the 12-month reunion when compared to pre and post camp measurements. ^ Conclusion: Kamp K'aana has consistently shown short-term reductions in weight, BMI, BMI percentile, and BMI z-score. Results from analysis of long-term data suggest that this intervention had beneficial effects on body composition in an ethnically diverse population of obese children. Further research which includes a control group, larger sample size, and cost-analysis should be conducted.^

The impact of ocean acidification and warming on the skeletal mechanical properties of the sea urchin Paracentrotus lividus from laboratory and field observations

Increased atmospheric CO2 concentration is leading to changes in the carbonate chemistry and the temperature of the ocean. The impact of these processes on marine organisms will depend on their ability to cope with those changes, particularly the maintenance of calcium carbonate structures. Both a laboratory experiment (long-term exposure to decreased pH and increased temperature) and collections of individuals from natural environments characterized by low pH levels (individuals from intertidal pools and around a CO2 seep) were here coupled to comprehensively study the impact of near-future conditions of pH and temperature on the mechanical properties of the skeleton of the euechinoid sea urchin Paracentrotus lividus. To assess skeletal mechanical properties, we characterized the fracture force, Young's modulus, second moment of area, material nanohardness, and specific Young's modulus of sea urchin test plates. None of these parameters were significantly affected by low pH and/or increased temperature in the laboratory experiment and by low pH only in the individuals chronically exposed to lowered pH from the CO2 seeps. In tidal pools, the fracture force was higher and the Young's modulus lower in ambital plates of individuals from the rock pool characterized by the largest pH variations but also a dominance of calcifying algae, which might explain some of the variation. Thus, decreases of pH to levels expected for 2100 did not directly alter the mechanical properties of the test of P. lividus. Since the maintenance of test integrity is a question of survival for sea urchins and since weakened tests would increase the sea urchins' risk of predation, our findings indicate that the decreasing seawater pH and increasing seawater temperature expected for the end of the century should not represent an immediate threat to sea urchins vulnerability

Work instability. Presentation of an empirical model about its psychological impact

Research on the impact that work instability has on workers has the limitation of assess the relations among different variables separately, without examining the possible mediation relationships that can exists between them. The aim of this article is to test a conceptual model of the mediating relations between the uneasiness due to work instability and the psychological impact, in the framework of interactive stress theory, conducting a Path Analysis. 191 workers participated on the study, with a mean age of 31 years-old (SD = 11). Results showed that the proposed model didn't fit to the data. Alternative models were explored, consistent with the original conceptual model and the empiric evidence. A new causal model is proposed, where Uneasiness due to Work Instability as an independent variable, Personal Strain and Personal Resources as intervenient variables, and Anger, Hopelessness, and Satisfaction as dependent ones. The theoretical and empirical importance of the resulting model is discussed.

Educational orientation regarding vocabulary and literacy access : Evaluating the impact of an intervention program designed to promote early learning at home

El estudio evalúa el impacto de un programa de promoción del desarrollo lingüístico y cognitivo para niños de 5 años implementado según dos modalidades: una que implicó acciones de alfabetización familiar en los hogares de los niños (modalidad intensiva) y otra que incluyó la participación de los niños en las salas de jardín de infantes (modalidad extensiva). La evaluación del impacto se realizó por medio de un diseño pre-test ? post-test. Se tomaron pruebas de vocabulario receptivo (VR), producción de categorías (PC) y escritura a una muestra de 214 niños participantes de la modalidad intensiva, 69 participantes de la modalidad extensiva y un grupo control de no participó del programa (49 niños). Los resultados mostraron que la participación en la modalidad intensiva implicó un mayor incremento en las habilidades infantiles de VR, PC que en la modalidad extensiva. A su vez ambas modalidades experimentales mostraron un mayor incremento en las variables examinadas respecto de las observadas en el grupo control. No se detectaron efectos de la escolaridad de la madre y la asistencia previa al jardín. Los resultados mostraron correlaciones significativas entre todas las variables analizadas y el valor predictivo de los puntajes en VR a principio de año respecto de los puntajes en VR y escritura a fin de año.

Work instability. Presentation of an empirical model about its psychological impact

Research on the impact that work instability has on workers has the limitation of assess the relations among different variables separately, without examining the possible mediation relationships that can exists between them. The aim of this article is to test a conceptual model of the mediating relations between the uneasiness due to work instability and the psychological impact, in the framework of interactive stress theory, conducting a Path Analysis. 191 workers participated on the study, with a mean age of 31 years-old (SD = 11). Results showed that the proposed model didn't fit to the data. Alternative models were explored, consistent with the original conceptual model and the empiric evidence. A new causal model is proposed, where Uneasiness due to Work Instability as an independent variable, Personal Strain and Personal Resources as intervenient variables, and Anger, Hopelessness, and Satisfaction as dependent ones. The theoretical and empirical importance of the resulting model is discussed.

Educational orientation regarding vocabulary and literacy access : Evaluating the impact of an intervention program designed to promote early learning at home

El estudio evalúa el impacto de un programa de promoción del desarrollo lingüístico y cognitivo para niños de 5 años implementado según dos modalidades: una que implicó acciones de alfabetización familiar en los hogares de los niños (modalidad intensiva) y otra que incluyó la participación de los niños en las salas de jardín de infantes (modalidad extensiva). La evaluación del impacto se realizó por medio de un diseño pre-test ? post-test. Se tomaron pruebas de vocabulario receptivo (VR), producción de categorías (PC) y escritura a una muestra de 214 niños participantes de la modalidad intensiva, 69 participantes de la modalidad extensiva y un grupo control de no participó del programa (49 niños). Los resultados mostraron que la participación en la modalidad intensiva implicó un mayor incremento en las habilidades infantiles de VR, PC que en la modalidad extensiva. A su vez ambas modalidades experimentales mostraron un mayor incremento en las variables examinadas respecto de las observadas en el grupo control. No se detectaron efectos de la escolaridad de la madre y la asistencia previa al jardín. Los resultados mostraron correlaciones significativas entre todas las variables analizadas y el valor predictivo de los puntajes en VR a principio de año respecto de los puntajes en VR y escritura a fin de año.

Work instability. Presentation of an empirical model about its psychological impact

Research on the impact that work instability has on workers has the limitation of assess the relations among different variables separately, without examining the possible mediation relationships that can exists between them. The aim of this article is to test a conceptual model of the mediating relations between the uneasiness due to work instability and the psychological impact, in the framework of interactive stress theory, conducting a Path Analysis. 191 workers participated on the study, with a mean age of 31 years-old (SD = 11). Results showed that the proposed model didn't fit to the data. Alternative models were explored, consistent with the original conceptual model and the empiric evidence. A new causal model is proposed, where Uneasiness due to Work Instability as an independent variable, Personal Strain and Personal Resources as intervenient variables, and Anger, Hopelessness, and Satisfaction as dependent ones. The theoretical and empirical importance of the resulting model is discussed.

Educational orientation regarding vocabulary and literacy access : Evaluating the impact of an intervention program designed to promote early learning at home

El estudio evalúa el impacto de un programa de promoción del desarrollo lingüístico y cognitivo para niños de 5 años implementado según dos modalidades: una que implicó acciones de alfabetización familiar en los hogares de los niños (modalidad intensiva) y otra que incluyó la participación de los niños en las salas de jardín de infantes (modalidad extensiva). La evaluación del impacto se realizó por medio de un diseño pre-test ? post-test. Se tomaron pruebas de vocabulario receptivo (VR), producción de categorías (PC) y escritura a una muestra de 214 niños participantes de la modalidad intensiva, 69 participantes de la modalidad extensiva y un grupo control de no participó del programa (49 niños). Los resultados mostraron que la participación en la modalidad intensiva implicó un mayor incremento en las habilidades infantiles de VR, PC que en la modalidad extensiva. A su vez ambas modalidades experimentales mostraron un mayor incremento en las variables examinadas respecto de las observadas en el grupo control. No se detectaron efectos de la escolaridad de la madre y la asistencia previa al jardín. Los resultados mostraron correlaciones significativas entre todas las variables analizadas y el valor predictivo de los puntajes en VR a principio de año respecto de los puntajes en VR y escritura a fin de año.

Impact of seasonality-adjusted flexible microcredit on repayment and food consumption : experimental evidence from rural Bangladesh

The mismatch between credit repayments and income seasonality poses a challenge for microfinance institutions (MFIs) working in developing countries. For instance, in northern Bangladesh, income and consumption downfalls during the lean season after the transplanting of major paddy crops are a serious threat to a household's economy. Poor landless agricultural wage laborers suffer the most owing to this seasonality as they face difficulties in smoothing their consumption. However, in designing microcredit products, MFIs do not usually provide flexibility or seasonal adjustment during the lean season. This is mainly because MFIs are afraid that such flexibility might break the repayment discipline of borrowers, resulting in higher default rates. We thus conducted a randomized controlled trial in 2011-12 in northern Bangladesh to empirically test whether seasonality-adjusted flexible microcredit leads to an increase in repayment problems for MFIs as well as whether it can increase and stabilize consumption of borrower households. Our results suggest no statistically discernible difference among the treatment arms in case of default, overdue amount, or repayment frequency. On the other hand, we find no positive impact of repayment flexibility on immediate food consumption during the period of seasonality, except for in-kind full moratorium treatment group. After a year of initial intervention, however, we see positive changes in food intake during the lean season. Thus, our preliminary results are in favor of seasonality-adjusted flexible microcredit.

Modelling the Impact of Built Environment, Geographical Scales and Latent Constructs On Individual Travel Behaviour

La relación entre la estructura urbana y la movilidad ha sido estudiada desde hace más de 70 años. El entorno urbano incluye múltiples dimensiones como por ejemplo: la estructura urbana, los usos de suelo, la distribución de instalaciones diversas (comercios, escuelas y zonas de restauración, parking, etc.). Al realizar una revisión de la literatura existente en este contexto, se encuentran distintos análisis, metodologías, escalas geográficas y dimensiones, tanto de la movilidad como de la estructura urbana. En este sentido, se trata de una relación muy estudiada pero muy compleja, sobre la que no existe hasta el momento un consenso sobre qué dimensión del entorno urbano influye sobre qué dimensión de la movilidad, y cuál es la manera apropiada de representar esta relación. Con el propósito de contestar estas preguntas investigación, la presente tesis tiene los siguientes objetivos generales: (1) Contribuir al mejor entendimiento de la compleja relación estructura urbana y movilidad. y (2) Entender el rol de los atributos latentes en la relación entorno urbano y movilidad. El objetivo específico de la tesis es analizar la influencia del entorno urbano sobre dos dimensiones de la movilidad: número de viajes y tipo de tour. Vista la complejidad de la relación entorno urbano y movilidad, se pretende contribuir al mejor entendimiento de la relación a través de la utilización de 3 escalas geográficas de las variables y del análisis de la influencia de efectos inobservados en la movilidad. Para el análisis se utiliza una base de datos conformada por tres tipos de datos: (1) Una encuesta de movilidad realizada durante los años 2006 y 2007. Se obtuvo un total de 943 encuestas, en 3 barrios de Madrid: Chamberí, Pozuelo y Algete. (2) Información municipal del Instituto Nacional de Estadística: dicha información se encuentra enlazada con los orígenes y destinos de los viajes recogidos en la encuesta. Y (3) Información georeferenciada en Arc-GIS de los hogares participantes en la encuesta: la base de datos contiene información respecto a la estructura de las calles, localización de escuelas, parking, centros médicos y lugares de restauración. Se analizó la correlación entre e intra-grupos y se modelizaron 4 casos de atributos bajo la estructura ordinal logit. Posteriormente se evalúa la auto-selección a través de la estimación conjunta de las elecciones de tipo de barrio y número de viajes. La elección del tipo de barrio consta de 3 alternativas: CBD, Urban y Suburban, según la zona de residencia recogida en las encuestas. Mientras que la elección del número de viajes consta de 4 categorías ordinales: 0 viajes, 1-2 viajes, 3-4 viajes y 5 o más viajes. A partir de la mejor especificación del modelo ordinal logit. Se desarrolló un modelo joint mixed-ordinal conjunto. Los resultados indican que las variables exógenas requieren un análisis exhaustivo de correlaciones con el fin de evitar resultados sesgados. ha determinado que es importante medir los atributos del BE donde se realiza el viaje, pero también la información municipal es muy explicativa de la movilidad individual. Por tanto, la percepción de las zonas de destino a nivel municipal es considerada importante. En el contexto de la Auto-selección (self-selection) es importante modelizar conjuntamente las decisiones. La Auto-selección existe, puesto que los parámetros estimados conjuntamente son significativos. Sin embargo, sólo ciertos atributos del entorno urbano son igualmente importantes sobre la elección de la zona de residencia y frecuencia de viajes. Para analizar la Propensión al Viaje, se desarrolló un modelo híbrido, formado por: una variable latente, un indicador y un modelo de elección discreta. La variable latente se denomina “Propensión al Viaje”, cuyo indicador en ecuación de medida es el número de viajes; la elección discreta es el tipo de tour. El modelo de elección consiste en 5 alternativas, según la jerarquía de actividades establecida en la tesis: HOME, no realiza viajes durante el día de estudio, HWH tour cuya actividad principal es el trabajo o estudios, y no se realizan paradas intermedias; HWHs tour si el individuo reaiza paradas intermedias; HOH tour cuya actividad principal es distinta a trabajo y estudios, y no se realizan paradas intermedias; HOHs donde se realizan paradas intermedias. Para llegar a la mejor especificación del modelo, se realizó un trabajo importante considerando diferentes estructuras de modelos y tres tipos de estimaciones. De tal manera, se obtuvieron parámetros consistentes y eficientes. Los resultados muestran que la modelización de los tours, representa una ventaja sobre la modelización de los viajes, puesto que supera las limitaciones de espacio y tiempo, enlazando los viajes realizados por la misma persona en el día de estudio. La propensión al viaje (PT) existe y es específica para cada tipo de tour. Los parámetros estimados en el modelo híbrido resultaron significativos y distintos para cada alternativa de tipo de tour. Por último, en la tesis se verifica que los modelos híbridos representan una mejora sobre los modelos tradicionales de elección discreta, dando como resultado parámetros consistentes y más robustos. En cuanto a políticas de transporte, se ha demostrado que los atributos del entorno urbano son más importantes que los LOS (Level of Service) en la generación de tours multi-etapas. la presente tesis representa el primer análisis empírico de la relación entre los tipos de tours y la propensión al viaje. El concepto Propensity to Travel ha sido desarrollado exclusivamente para la tesis. Igualmente, el desarrollo de un modelo conjunto RC-Number of trips basado en tres escalas de medida representa innovación en cuanto a la comparación de las escalas geográficas, que no había sido hecha en la modelización de la self-selection. The relationship between built environment (BE) and travel behaviour (TB) has been studied in a number of cases, using several methods - aggregate and disaggregate approaches - and different focuses – trip frequency, automobile use, and vehicle miles travelled and so on. Definitely, travel is generated by the need to undertake activities and obtain services, and there is a general consensus that urban components affect TB. However researches are still needed to better understand which components of the travel behaviour are affected most and by which of the urban components. In order to fill the gap in the research, the present dissertation faced two main objectives: (1) To contribute to the better understanding of the relationship between travel demand and urban environment. And (2) To develop an econometric model for estimating travel demand with urban environment attributes. With this purpose, the present thesis faced an exhaustive research and computation of land-use variables in order to find the best representation of BE for modelling trip frequency. In particular two empirical analyses are carried out: 1. Estimation of three dimensions of travel demand using dimensions of urban environment. We compare different travel dimensions and geographical scales, and we measure self-selection contribution following the joint models. 2. Develop a hybrid model, integrated latent variable and discrete choice model. The implementation of hybrid models is new in the analysis of land-use and travel behaviour. BE and TB explicitly interact and allow richness information about a specific individual decision process For all empirical analysis is used a data-base from a survey conducted in 2006 and 2007 in Madrid. Spatial attributes describing neighbourhood environment are derived from different data sources: National Institute of Statistics-INE (Administrative: municipality and district) and GIS (circular units). INE provides raw data for such spatial units as: municipality and district. The construction of census units is trivial as the census bureau provides tables that readily define districts and municipalities. The construction of circular units requires us to determine the radius and associate the spatial information to our households. The first empirical part analyzes trip frequency by applying an ordered logit model. In this part is studied the effect of socio-economic, transport and land use characteristics on two travel dimensions: trip frequency and type of tour. In particular the land use is defined in terms of type of neighbourhoods and types of dwellers. Three neighbourhood representations are explored, and described three for constructing neighbourhood attributes. In particular administrative units are examined to represent neighbourhood and circular – unit representation. Ordered logit models are applied, while ordinal logit models are well-known, an intensive work for constructing a spatial attributes was carried out. On the other hand, the second empirical analysis consists of the development of an innovative econometric model that considers a latent variable called “propensity to travel”, and choice model is the choice of type of tour. The first two specifications of ordinal models help to estimate this latent variable. The latent variable is unobserved but the manifestation is called “indicators”, then the probability of choosing an alternative of tour is conditional to the probability of latent variable and type of tour. Since latent variable is unknown we fit the integral over its distribution. Four “sets of best variables” are specified, following the specification obtained from the correlation analysis. The results evidence that the relative importance of SE variables versus BE variables depends on how BE variables are measured. We found that each of these three spatial scales has its intangible qualities and drawbacks. Spatial scales play an important role on predicting travel demand due to the variability in measures at trip origin/destinations within the same administrative unit (municipality, district and so on). Larger units will produce less variation in data; but it does not affect certain variables, such as public transport supply, that are more significant at municipality level. By contrast, land-use measures are more efficient at district level. Self-selection in this context, is weak. Thus, the influence of BE attributes is true. The results of the hybrid model show that unobserved factors affect the choice of tour complexity. The latent variable used in this model is propensity to travel that is explained by socioeconomic aspects and neighbourhood attributes. The results show that neighbourhood attributes have indeed a significant impact on the choice of the type of tours either directly and through the propensity to travel. The propensity to travel has a different impact depending on the structure of each tour and increases the probability of choosing more complex tours, such as tours with many intermediate stops. The integration of choice and latent variable model shows that omitting important perception and attitudes leads to inconsistent estimates. The results also indicate that goodness of fit improves by adding the latent variable in both sequential and simultaneous estimation. There are significant differences in the sensitivity to the latent variable across alternatives. In general, as expected, the hybrid models show a major improvement into the goodness of fit of the model, compared to a classical discrete choice model that does not incorporate latent effects. The integrated model leads to a more detailed analysis of the behavioural process. Summarizing, the effect that built environment characteristics on trip frequency studied is deeply analyzed. In particular we tried to better understand how land use characteristics can be defined and measured and which of these measures do have really an impact on trip frequency. We also tried to test the superiority of HCM on this field. We can concluded that HCM shows a major improvement into the goodness of fit of the model, compared to classical discrete choice model that does not incorporate latent effects. And consequently, the application of HCM shows the importance of LV on the decision of tour complexity. People are more elastic to built environment attributes than level of services. Thus, policy implications must take place to develop more mixed areas, work-places in combination with commercial retails.