Confirmatory Validation of an Evaluation Instrument for Interventions Based on the Healthy Habits App Healthy Jeart with Adolescents

  Citation: Merino-Godoy, M.Á.; Yot-Domínguez, C.; Conde-Jiménez, J.; de la Calle-Cabrera, A.M. Confirmatory Validation of an Evaluation Instrument for Interventions Based on the Healthy Habits App Healthy Jeart with Adolescents. J. Pers. Med. 2022,12, 470. https://doi.org/10.3390/ jpm12030470 Academic Editor: Amir Hajjam El Hassani Received: 19 January 2022 Accepted: 11 March 2022 Published: 15 March 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). Journal of Personalized Medicine Article Confirmatory Validation of an Evaluation Instrument for Interventions Based on the Healthy Habits App Healthy Jeart with Adolescents MaríaÁngeles Merino-Godoy 1, Carmen Yot-Domínguez 2,* , Jesús Conde-Jiménez 3 and Ana María de la Calle-Cabrera 4 1Department of Nursing, University of Huelva, 21071 Huelva, Spain; [email protected] 2Department of Didactics and Educational Organization, University of Seville, 41013 Seville, Spain 3Department of Theory and History of Education and Social Pedagogy, University of Seville, 41013 Seville, Spain; [email protected] 4Department of Didactics of Language and Literature and Integrated Philologies, University of Seville, 41013 Seville, Spain; [email protected] *Correspondence: [email protected] Abstract: Mobile devices are widely used among young people, and their use for health promotion is in-creasing. Healthy Jeart is a mobile application aimed at promoting healthy life habits among people aged 8–16 years. The aim of this study was to develop and validate an instrument that allows evaluating the healthy knowledge, habits and attitudes learned by adolescents aged 12–16 years through the Healthy Jeart application. Attending to the content of Healthy Jeart, a first version of the evaluation instrument was generated. It was subjected to expert judgement. The second version was administered to 429 adolescents from six educational centres of Andalusia to carry out the validation of the construct through exploratory and confirmatory factor analyses. After exploration, a six-factor model was confirmed, with a very adequate level of fit and good internal consistency. The six factors were: (1) knowledge about eating and physical activity, (2) habits about eating and physical activity, (3) emotional health, (4) consumption of alcohol and drugs, (5) social relationships and (6) sexual activities and use of technologies. There are at least four instruments that could be used to measure health-promoting behaviours. However, this new instrument was created ad hoc. It measures exactly the results that can be expected. Healthy Jeart will now have a valid and reliable evaluation instrument: Ev-HealthyJRT v.1.0. Young people, teachers and other professionals who carry out health-promotion interventions based on Healthy Jeart with adolescents will have at their disposal an instrument integrated in this app that allows verifying the learning results. However, the validated instrument can be used for evaluation in other interventions, as long as the multiple and essential aspects of a healthy living are addressed as in Healthy Jeart. Keywords: adolescents; eHealth app; health interventions; health promotion; instrument development 1. Introduction Healthy Jeart is a mobile application aimed at promoting healthy life habits among people aged 8–16 years. It is available, free of charge, for Android and iOS devices. It has been considered as a “healthy app” by the Andalusian Agency of Health Quality. This distinction is the first in Spain to recognise the quality and safety of health applications. Continuous work is carried out on Healthy Jeart to keep it up to date and functioning properly. This study presents the creation and validation of an instrument that allows evaluating the learning results about health in adolescents aged 12–16 years. This population group works in it on seven areas of health, of which two are restricted for children aged 8–11 years. The mentioned instrument will be implemented in the application to facilitate the verification of knowledge, attitudes and habits before, during and after the use of Healthy Jeart. Further J. Pers. Med. 2022,12, 470. https://doi.org/10.3390/jpm12030470 https://www.mdpi.com/journal/jpm J. Pers. Med. 2022,12, 470 2 of 16 information about the project can be found at http://www.healthyjeart.com/ (accessed on 14 March 2022). 2. Background Adolescence is an ideal stage to promote a healthy lifestyle and correct unhealthy habits [ 1 ]. In general, adolescents do not have healthy lifestyles [ 2 ]. Moreover, during the transition to young adulthood (13–24 years), their healthy behaviours decline, giving rise to significantly less healthy practices [ 3 ]. Therefore, it is urgent to help them to improve their habits and sensitise them about the importance of avoiding risks to their present and future health state [4]. Adolescents should know that the early adoption of healthy habits strongly contributes to a better future quality of life [5]. The progressive development of educational interventions aimed at increasing the health of young people, in the school context and in other scopes, has generated the need to create valid instruments for the evaluation of health-promoting behaviours. Evaluation is an essential element of the design and development of interventions to promote lifestyles among adolescents. Therefore, the creation of valid instruments is an important challenge. Thus, there are different instruments related to healthy lifestyles in adolescents, such as those of Gillis [ 6 ] (ALQ, Adolescent Lifestyle Questionnaire), Chen et al. [ 7 ] (Adolescent Health Promotion Scale, AHPS), Hendricks et al. [ 8 ] (ALP, Adolescent Lifestyle Profile) and Mahon et al. [ 9 , 10 ] (revised PLQ, Personal Lifestyle Questionnaire for adolescents). The Adolescent Lifestyle Questionnaire is a 43-item instrument designed to measure healthy lifestyle practices in adolescents. It focuses on identity awareness (nine items), nutrition (eight items), physical participation (four items), safety (seven items), health awareness (four items), social support (seven items) and stress management (four items). The Adolescent Health Promotion Scale has 40 items and about six domains of healthy lifestyles (social support, life appreciation, health responsibility, nutritional behaviours, exercise behaviours and stress management). The Adolescent Lifestyle Profile scale initially had 42 items, and two more items were eventually added. The resulting new scale, Adolescent Lifestyle Profile Revised 2 (ALP-R2), has 44 items and seven dimensions (health responsibility, physical activity, nutrition, positive life perspective, interpersonal relationships, stress management and spiritual health). The Personal Lifestyle Questionnaire (PLQ) was developed by Muhlenkamp and Brown [ 11 ] to measure positive health practices in adults and older adolescents. Its version for early adolescents is a 24-item scale that is internally organised in two factors (Health Promotion Practices and Health Protective Practices) and six subscales (nutrition, four items; relaxation, five items; exercise, four items; health promotion, four items; safety, four items; and substance use, three items). These have been revised, adapted and validated transculturally [ 12 – 15 ]. In addition to these instruments, others such as ENHASA [ 16 ] are considered effective questionnaires. This questionnaire assesses the main modifiable health behaviours among adolescents aged 12–14 years related to eating (eight items), physical activity (four items), new technologies (seven items), and environment (seven items). Its use is indicated for schools, due to the specificity of some of its items, such as “brings lunch from home”. Currently, health interventions are being mediated by technology [ 17 ]. Mobile devices are widely used among young people, and their use for health promotion is increasing. Thus, in the scientific literature, we find documented interventions with eHealth apps, such as that of Benavides et al. [ 18 ]. Specifically, eHealth interventions that address multiple lifestyle risk behaviours have been confirmed as effective at improving physical activity and eating, although their effects are small and evident only immediately after the intervention [ 19 ]. The research studies on health promotion with applications are still limited; however, the use of applications seems to be viable and promising [ 20 ]. Fedele et al. [ 21 ] concluded that mobile health interventions have a significant effect, even though small, on the health of young people. They improve several lifestyle domains, such as physical activity [22], eating, health responsibility and positive life perspective [23]. J. Pers. Med. 2022,12, 470 3 of 16 Healthy Jeart Healthy Jeart is a free health application for children and adolescents aged 8–16 years. Its first version was published in 2018. Before that, the Andalusian Agency of Health Quality (ACSA) evaluated it as a “healthy app” [ 24 ]. This app was designed by researchers of the Universities of Seville and Huelva [ 25 ] to promote healthy lifestyles with a global approach on health. It fits the needs and concerns of young people, as the design process was initiated with the development of nominal groups with which relevant topics to address were identified [26]. Minors can find in it clear, brief, simple and understandable messages (called tips), with practical advice and suggestions, with a theoretical basis, on different areas of health. Young people aged 12–16 years have information about the following seven areas: physical activity (physical state, physical exercise, sport), eating (nutrition, food and drinks), physical well-being (sleep, personal hygiene and safety, time management), psychological well-being (self-esteem and self-concept, emotions, social skills), toxic substances and addictions (substances such as alcohol, tobacco, cannabis), affection-sex (sexuality, couple relationships, gender violence) and new technologies (use and abuse of technologies, social networks). Children aged 8–11 years do not have access to the areas on toxic substances and addiction and affection-sex. The aim is to help them expand their knowledge in every area, develop favourable attitudes and become aware of how they can improve their habits and adopt healthy behaviours. Experts in the corresponding areas have approved the tips of each of the areas. All of them have been written for children and young people, using strategies to help them remember, such as rhymes and jokes (in Figure 1two examples of tips from the app are shown). J. Pers. Med. 2022, 12, x FOR PEER REVIEW 3 of 16 2.1. Healthy Jeart Healthy Jeart is a free health application for children and adolescents aged 8–16 years. Its first version was published in 2018. Before that, the Andalusian Agency of Health Quality (ACSA) evaluated it as a “healthy app” [24]. This app was designed by researchers of the Universities of Seville and Huelva [25] to promote healthy lifestyles with a global approach on health. It fits the needs and concerns of young people, as the design process was initiated with the development of nominal groups with which relevant topics to address were identified [26]. Minors can find in it clear, brief, simple and understandable messages (called tips), with practical advice and suggestions, with a theoretical basis, on different areas of health. Young people aged 12–16 years have information about the following seven areas: physical activity (physical state, physical exercise, sport), eating (nutrition, food and drinks), physical well-being (sleep, personal hygiene and safety, time management), psychological well-being (self-esteem and self-concept, emotions, social skills), toxic substances and addictions (substances such as alcohol, tobacco, cannabis), affection-sex (sexuality, couple relationships, gender violence) and new technologies (use and abuse of technologies, social networks). Children aged 8–11 years do not have access to the areas on toxic substances and addiction and affection-sex. The aim is to help them expand their knowledge in every area, develop favourable attitudes and become aware of how they can improve their habits and adopt healthy behaviours. Experts in the corresponding areas have approved the tips of each of the areas. All of them have been written for children and young people, using strategies to help them remember, such as rhymes and jokes (in Figure 1 two examples of tips from the app are shown). Figure 1. Examples of app tips. In addition to the tips, an attractive game helps them to recognise the different basic and important aspects of health. Jeart, a heart-shaped friendly alien, is the main character. Jeart must keep moving by making a vertical tour. As it goes up, Jeart must come into contact with objects that represent aspects of the different areas that favour health (e.g., sports, water, sleep) and avoid products and activities that are bad for health (e.g., drugs, Figure 1. Examples of app tips. In addition to the tips, an attractive game helps them to recognise the different basic and important aspects of health. Jeart, a heart-shaped friendly alien, is the main character. Jeart must keep moving by making a vertical tour. As it goes up, Jeart must come into contact with objects that represent aspects of the different areas that favour health (e.g., sports, water, sleep) and avoid products and activities that are bad for health (e.g., drugs, sugar, soft drinks). In a forum where healthy ideas can be shared, the users can obtain rewards for the game. J. Pers. Med. 2022,12, 470 4 of 16 Healthy Jeart is designed for use in the school context, although it can also be used in other areas. Therefore, this application provides teachers with proposals of educational activities for each of the areas. The work on the content addressed in the app extends to the classroom under the guidance and counseling of the teacher through applied specific activities, which can be performed individually or in small or large groups. Moreover, Healthy Jeart also provides monthly health challenges in which groups-classes can participate and compete with those of other educational centres. These are propositions of activities that must be conducted in a continuous manner, with the aim of consolidating habits such as relaxation and hydration, among others. The research team involved in the design and production of the application have worked in the writing and validation of an evaluation instrument that allows measuring the knowledge, habits and attitudes about health that are addressed in the app for young people aged 12–16 years. It is necessary to accompany the content and work propositions with an instrument that accurately measures the results, specifically considering those that can be achieved. Resorting to non-specific instruments would distort the initial, continuous or final evaluation in interventions with Healthy Jeart. The few instruments available to date do not fully fit our evaluation purpose. The Adolescent Lifestyle Questionnaire [ 6 ] includes a domain of stress management, which is not directly addressed in Healthy Jeart. Its safety domain considers the rejection of the consumption of substances that are harmful to health and safety in sexual relations, although, on the latter, there are only two items, which is insufficient to cover the affection-sex area of Healthy Jeart. In addition, this instrument does not expressly refer to the responsible and safe use of mobile devices and digital social networks. Similarly, the Adolescent Lifestyle Profile Revised 2 [ 8 , 12 , 14 ] and the Adolescent Health Promotion Scale [ 7 ] do not cover the new technologies area of Healthy Jeart. If those instruments were used, the areas of toxic substances and addictions and affection-sex would not be evaluated. In ALP-R2, there are items that do not correspond to the content of the other areas, such as “I seek guidance from school counselor when needed” and “I attend a group that shares my spiritual beliefs”. Spiritual health is not an area of Healthy Jeart. The revised Personal Lifestyle Questionnaire for adolescents [ 9 ] does not address areas expressly worked in the app, such as affection-sex and new technology. With it, very specific behaviours that are not promoted in the app would be valued as “limit caffeine intake to three cups daily (includes sodas, coffee, and tea)”. The purpose is to create a self-report instrument that addresses the current health areas included in the app, adjusts to the real needs and interests of the adolescents and can be used in the context of mobile interventions, without being limited to the context of the school. 3. Method and Materials The general aim of this study was to design and validate an instrument that allows evaluating the healthy knowledge, habits and attitudes learned by adolescents aged 12–16 years through Healthy Jeart. This is a quantitative, cross-sectional study. The creation of the instrument involved work that was clearly differentiated into two phases. First, we wrote the items and validated the content of the instrument. Second, we conducted the validation of an explanatory model that supports the instrument. Primary identification of the items to incorporate in the new instrument was accomplished using a complete review of the app. Attending to the content of Healthy Jeart, the first version of the evaluation instrument was generated. As was already mentioned, this content has theoretical foundation and was validated when the app was designed and produced by experts. It was also evaluated by the ACSA. From thorough analysis of the tips, activities and challenges available in the application, 72 items were extracted. These items correspond to the different areas of the app in the following manner: 1. Physical activity (nine items); 2. Eating (eleven items); 3. Physical well-being (nine items); 4. Psychological well-being (fifteen items); 5. Toxic substances and addictions (seven items); 6. Affection-sex (eleven items), and 7. New technologies (ten items). These are some of the items: “I avoid J. Pers. Med. 2022,12, 470 5 of 16 doing sedentary activities like watching TV or play videogames in my spare time”; “I have personal hygiene habits like brushing my teeth after each meal” and “I know what to do in situations of gender violence”. The revision of the standardised instruments available in the scientific literature inspired the wording of the items. Thus, similarities can be found with these. This instrument was subjected to expert judgement for content validation. A total of 15 experts (eight women and seven men; mean age: 46 years) were asked through a digital questionnaire. These experts worked in the Andalusian Healthcare Service (four), local administration (three), educational centres and universities (six) and non-for-profit organisations (two). The expert group valued from 1 (Totally disagree) to 10 (Totally agree) the following criteria per item: clarity in the writing (the item is clearly written); internal coherence (the writing of the item is coherent); response induction (the writing of the item induces the answer); suitability of the language with the level of the respondents (the writing of the item suits the age range of 12–16 years), and target evaluation (the item evaluates exactly what it expresses). We considered that a mean score equal to or higher than 8 points per item and criterion showed an adequate degree of agreement. All the items surpassed this mean score in all the different criteria. Moreover, the experts expressed their perception toward the instrument in its entirety through the following five items: 1. The instrument contains clear and precise instructions to be answered; 2. The items allow evaluating the content of the Healthy Jeart app; 3. The items are distributed in a logical manner; 4. The items are organised correctly, and 5. The items are free of spelling errors. The degree of agreement with each of the items was expressed in a scale of 1 (Totally disagree) to 10 (Totally agree). Table 1presents the means obtained for each item, which were all above nine points. The standard deviation was below 1, indicating little variation. Table 1. Descriptive statistics derived from the validation of the content through the expert judgement. The Instrument Contains Clear and Precise Instructions to Be Responded The Items Allow Evaluating the Content of the Healthy Jeart App The Items Are Distributed in a Logical Manner The Items Are Organised Correctly The Items Are Free of Spelling Errors Mean 9.20 9.33 9.67 9.60 9.53 Standard Deviation 0.941 0.816 0.488 0.507 0.640 Minimum 7 8 9 9 8 Maximum 10 10 10 10 10 However, along with the valuations, the experts made qualitative observations for each item and for the instrument in its entirety. Some of such observations suggested minor changes in the writing of the items to better suit the age of the end recipients, such as: “I would replace I opt with I choose”; “I would also add walking as an example”; “Indicate the main foods of the Mediterranean diet”, and “I would replace continuity with perform regularly”. Other comments encouraged the formulation of new items, e.g., “These are two items in one. I can differentiate the groups of foods, but not the amount, and that could make the users doubt”. Consequently, the writing of all the items was revised attending to the suggestions and three new items were included in the instrument. In the eating area, the item “I differentiate the groups of foods and the amount of them that we must consume daily, according to the food pyramid” was fragmented into the following two items “I differentiate the groups of foods of the food pyramid,” and “I know the amount of each food group that we should consume daily according to the food pyramid”. In this area, the following item was included, to satisfy the request of most of the experts: “I search for information to improve my nutrition”. In the physical well-being area, the item “I have healthy routines such as sleeping at least 8 h and drinking at least 2 litres of water every J. Pers. Med. 2022,12, 470 6 of 16 day” was replaced with the following two items: “I try to sleep at least 8 h every day” and “I drink at least 2 litres of water every day”. Thus, the second version of the instrument had 75 items, which represented each of the areas in the following manner: 1. Physical activity (nine items): the extent to which young people know the importance of practising physical activity and do so safely. 2. Eating (thirteen items): the knowledge that young people have about nutrition (food pyramid, saturated and unsaturated fats, ultra-processed foods, etc.) and the habits they must have to keep a healthy diet. 3. Physical well-being (ten items): the habits of hygiene, personal care and safety that young people have acquired to protect their own body. 4. Psychological well-being (fifteen items): the extent to which young people recognise their emotions and reflect on their needs, have a positive attitude toward problems and conflicts and nurture their relationships with others. 5. Toxic substances and addictions (seven items): the knowledge that young people have about alcohol and drugs and their attitude toward their consumption. 6. Affection-sex (eleven items): the extent to which young people recognise the link between sexuality and identity, their capacity to differentiate between love, attraction and infatuation, and what they know about how having consented and safe sexual relations. 7. New technologies (ten items): the use that young people make of mobile devices, how they behave in social networks, their capacity to recognise that the excessive use of mobile phones generates dependency, and that social networks can be dangerous. Next, after obtaining the permission to access the centres from the school principals and the participation consent authorised by the families, the instrument was administered to a sample of young people from six educational centres of the provinces of Huelva and Seville (Andalusia, Spain). The 75 items were presented in a five-point Likert scale of 1 (Totally disagree) to 5 (Totally agree), after a series of demographic questions, such as sex, course, educational centre and locality. The second version of the instrument and the document of informed consent of participation for the families were printed and sent to the principals of the participating educational centres. They distributed them among the tutor teachers in each group of students. These teachers were asked to inform the respective families and collect the signed consent forms, as well as to subsequently explain the purpose of the study and administer the instrument to the students in class. The students responded to the instrument in paper format during the tutoring hour assigned in the weekly timetable. In the classroom, one of the researchers of the team was present to offer support. Previously, they had to have interacted with the app at home. The data gathering process took place in April of the academic year 2020/2021. The responses were loaded to a database of the statistical software IBM SPSS Statistics version 26.0 in Spanish (Madrid, Spain). 3.1. Ethical Considerations This study strengthens the functionality of Healthy Jeart, with the creation and validation of Ev-HealthyJRT v.1.0, an evaluation instrument that will be implemented in it. For the validation of the evaluation instrument, it was necessary to collect self-reported data from the adolescents. To this end, authorisation from their families was obtained through a document of informed consent for participation. The anonymity of the answers was guaranteed at all times. No videos, images or audio recordings were taken during the filling of the questionnaire. The purpose of participation was to prove the validity of the instrument (assess its psychometric properties), and the teachers, students and families were informed about it. Students participated in the study freely. This study is framed within the research project “Design of a mobile phone application to educate the youth in healthy habits”. The Research Ethics Committee of the province of J. Pers. Med. 2022,12, 470 7 of 16 Huelva approved the project. The secretary of its Standing Committee recently issued a certificate dated 19 November 2021. 3.2. Sample/Participants The participants were recruited by non-probabilistic, convenience sampling. The inclusion criteria were: (1) age between 12 and 16 years; (2) enrolment in an educational centre of Huelva or Seville with authorisation of the principal to participate in the study and access to the centre; (3) informed consent of the parents or guardian prior to participating in the study, and (4) previous knowledge and usage of the app. The guaranteed sample size was of 300 students, i.e., the minimum required to perform a factor analysis. The sample of participants was constituted by 429 Secondary Education students from six educational centres of the Andalusian provinces of Huelva and Seville, of which three were public centres and the other three were private-charter centres. Regarding gender, the sample was equally distributed (51% boys and 49% girls). The age of the participants ranged between 12 and 16 years, with an average age of 14 years (SD: 1.156). Most of the students (89.5%) were between 12 and 15 years old. Of the four courses that integrate Secondary Education in Spain, 25.4% of the participants belonged to Year 8, 31.9% to Year 9, 30.8% to Year 10 and 11.9% to Year 11. 3.3. Data Analysis The data were subjected to a factor analysis (first exploratory and then confirmatory analysis), using JASP open source software version 0.11.1.0 in Spanish (Department of Psychological Methods, University of Amsterdam, Amsterdam, The Netherlands), to define an explanatory model about the study object. IBM SPSS Statistics software v.26 (Madrid, Spain) was used for the descriptive statistical analyses of the mean, variance, standard deviation, range, minimum and maximum values. At the procedural level, firstly, an exploratory factor analysis (EFA) was conducted. To estimate the number of factors, a parallel analysis was applied following the minimum residual estimation method and promax oblique rotation, obtaining a first approximation of the items to be included in the model. This first analysis helped to propose a reference structure. This analysis revealed a seven-factor model. However, the exclusion of items with a low factorial (below 0.4) resulted in readjustment to an explanatory model with six factors. Thus, this analysis revealed six factors for the organization of 32 items, with adequate fit indices (RMSEA = 0.037 and TLI = 0.83). After this exploration, those elements that did not have a factorial load between 0.4 and 1 were eliminated again, which reduced the initial theoretical design proposal from 75 items to 31. The confirmatory analysis work continued with these 31 items. Secondly, a confirmatory factor analysis (CFA) was performed. To determine the goodness of fit of this model, we analysed additional fit parameters, the goodness of fit index (GFI), and the coefficient of determination (R 2 ). We took as reference the criterion established by Hair et al. [ 27 ] and Hoyle [ 28 ], according to which, good values of fit are obtained if GFI and CFI ≥ 0.96, TLI ≥ 0.95, and RMSEA ≤ 0.05; moderate values if CFI, GFI and TLI ≥ 0.90 and RMSEA ≤ 0.08; and low values if CFI, GFI and TLI ≤ 0.90 and RMSEA ≤ 0.10. Regarding the Standardized Root Mean Square Residual (SRMR), we applied the criterion of Hair et al. [ 27 ] and Hu & Bentler [ 29 ], which consider that values equal to or lower than 0.08 indicate a good fit. Different tests were carried out for the exclusion of items and their reorganization in the factors, seeking the best possible fit of the model, taking into account the factor loadings and the theoretical dimensions (areas) worked on in the app. For this reason, the confirmed model included items with factor loadings greater than or around 0.4, since this contributed to the improvement of its fit indexes. J. Pers. Med. 2022,12, 470 8 of 16 4. Results The resulting model derives from the solution obtained in the CFA based on it to the first examination (EFA), undergoing adjustment in the items included (based on their factorial load) and their reorganization within the factors (based on the areas), as indicated in the previous section on data analysis. Thus, the model derived from this first exploration was tested, which is made up of six factors. Of the 31 items that were integrated into the six factors, 24 of these were included in the confirmed model, since a satisfactory adjustment solution was obtained. Likewise, a unidimensional model was estimated that presented worse fit indices χ2 (252, n= 429) = 1331.94, p< 0.001; RMSEA = 0.100 (95% CI [.095, 0.105], CFI = 0.61, NNFI = 0.57 , SRMR = 0.09. Consequently, based on the results obtained, the model of six correlated factors was chosen, made up of 24 items, showing better fit indices as detailed below. Factor 1 is knowledge about eating and physical activity. It includes four items from the physical activity and eating areas. Factor 2, habits about eating and physical activity, has three items also from these two areas. Emotional health is the third factor. Its four items come from the psychological well-being area. Consumption of alcohol and drugs (Factor 4) and social relationships and sexual activities (Factor 5) have four and five items, respectively. These factors fully correspond to the toxic substances and addictions and affection-sex areas in the same way as Factor 6 (use of technologies), with three items, and are associated with the new technologies area. First, theconfirmedmodelpresentsa Chi-squared distribution withvaluesof χ2= 470.013 and p-value < 0.001, as is shown in Table 2. Table 2. Chi-squared distribution. Model χ2df p Baseline model 3038.601 276 Factor model 470.013 237 <0.001 The Comparative Fit Index (CFI) and Tucker-Lewis Index (TLI) of the model, as presented in Table 3, obtained the following values: CFI = 0.916 and TLI = 0.902. Thus, the explanatory model obtained moderate parameters of fit in these indices. Table 3. Fit indices. Index Value Comparative Fit Index (CFI) 0.916 Tucker-Lewis Index (TLI) 0.902 Bentler-Bonett Non-normed Fit Index (NNFI) 0.902 Bentler-Bonett Normed Fit Index (NFI) 0.845 Parsimony Normed Fit Index (PNFI) 0.726 Bollen’s Relative Fit Index (RFI) 0.820 Bollen’s Incremental Fit Index (IFI) 0.917 Relative Noncentrality Index (RNI) 0.916 The Root Mean Square Error of Approximation (RMSEA) (in Table 4) obtained a value of 0.046 (95% CI: [0.040, 0.051]). Moreover, the confidence intervals are above 0, do not change sign and are under 0.06, indicating that the hypotheses of the model are not due to chance. Table 4also shows the values of Goodness of fit index (GFI), which was 0.914, and Standardised Root Mean Square Residual (SRMR), which was 0.061. Both indicate good results of goodness of fit. J. Pers. Med. 2022,12, 470 9 of 16 Table 4. Other fit measures. Metric Value Root mean square error of approximation (RMSEA) 0.046 RMSEA 90% CI lower bound 0.040 RMSEA 90% CI upper bound 0.051 RMSEA p-value 0.892 Standardized root mean square residual (SRMR) 0.061 Hoelter’s critical N (α= 0.05) 260.180 Hoelter’s critical N (α= 0.01) 274.614 Goodness of fit index (GFI) 0.914 McDonald fit index (MFI) 0.745 Expected cross validation index (ECVI) 1.564 Regarding the factor loading of the items of the confirmed model, these are around or above 0.4 (see Table 5). All these items were incorporated, due to the adequate indices and parameters of fit obtained, as was previously shown. As is shown in Table 5,p-values under 0.001 were obtained. This reveals that each item is different from the others. Moreover, the confidence intervals are positive and there is no change of sign, thus value 0 does not apply, i.e., this hypothesis does not admit chance. Table 5. Factor loadings. 95% Confidence Interval Factor Indicator Symbol Estimate Std. Error z-Value pLower Upper Factor 1 Item 1 λ11 0.382 0.042 9.176 <0.001 0.300 0.463 Item 2 λ12 0.768 0.056 13.706 <0.001 0.658 0.878 Item 3 λ13 0.741 0.058 12.791 <0.001 0.627 0.855 Item 4 λ14 0.577 0.060 9.648 <0.001 0.460 0.694 Factor 2 Item 5 λ21 0.635 0.062 10.201 <0.001 0.513 0.757 Item 6 λ22 0.815 0.057 14.378 <0.001 0.704 0.927 Item 7 λ23 0.567 0.066 8.598 <0.001 0.438 0.696 Item 8 λ24 0.725 0.069 10.467 <0.001 0.589 0.861 Factor 3 Item 9 λ31 0.782 0.050 15.506 <0.001 0.684 0.881 Item 10 λ32 0.718 0.054 13.375 <0.001 0.613 0.823 Item 11 λ33 0.505 0.058 8.631 <0.001 0.390 0.620 Item 12 λ34 0.559 0.070 7.997 <0.001 0.422 0.697 Factor 4 Item 13 λ41 0.652 0.033 20.037 <0.001 0.588 0.716 Item 14 λ42 0.697 0.033 21.274 <0.001 0.632 0.761 Item 15 λ43 0.463 0.043 10.687 <0.001 0.378 0.548 Item 16 λ44 0.428 0.054 7.928 <0.001 0.322 0.533 Factor 5 Item 17 λ51 0.620 0.039 15.763 <0.001 0.543 0.697 Item 18 λ52 0.536 0.034 15.986 <0.001 0.470 0.601 Item 19 λ53 0.588 0.046 12.782 <0.001 0.498 0.678 Item 20 λ54 0.538 0.048 11.141 <0.001 0.443 0.633 Item 21 λ55 0.515 0.040 12.943 <0.001 0.437 0.593 Factor 6 Item 22 λ61 0.548 0.033 16.831 <0.001 0.484 0.611 Item 23 λ62 0.394 0.050 7.842 <0.001 0.296 0.493 Item 24 λ63 0.542 0.041 13.257 <0.001 0.462 0.622 Table 6shows the residual variances by item. p-values below 0.001 were obtained, as well as positive confidence intervals without change of sign. 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