Translation and Validation of the Brazilian Version of the European Obesity Academy Questionnaire on Patients' Motivations for Seeking Metabolic and Bariatric Surgery.

PURPOSE: Understanding patients' motives for undergoing metabolic and bariatric surgery (MBS) is key to managing postoperative expectations. We aimed to translate and validate the 14-item European Obesity Academy Questionnaire on Expectations about Surgical Treatment (EOAQ-EST) to Brazilian Portuguese for research and clinical use. MATERIALS AND METHODS: This study included a total of 198 candidates for MBS at a reference academic hospital in Brazil from January 2021 to February 2022. We followed Beaton and Bombardier's guidelines for translation and cultural adaptation, including translation, back-translation, comparative analysis, expert review, pilot testing, and the creation of the final version of the questionnaire. Reliability was tested with McDonald's omega, and internal validity was assessed using confirmatory factor analysis (CFA). RESULTS: The final version was applied to 161 patients, 85% female, with a mean age of 46.4 ± 10.3 years and a mean BMI of 48.3 ± 8.2 kg/m2. Validity was supported by a bifactorial model (95% CI 0.044-0.104, p = 0.08), excluding one item (improved fertility) due to a floor effect. The reliability analysis showed that the 13 remaining items were internally consistent, with a McDonald's ω of 0.625. CONCLUSIONS: The Brazilian-Portuguese version of EOAQ-EST proved to be user-friendly, consistent, and reliable. This questionnaire may assist multidisciplinary teams in effectively addressing patients' expectations concerning metabolic and bariatric surgery (MBS) outcomes.

What Do Different People Look for in a Partner? Effects of Sex, Sexual Orientation, and Mating Strategies on Partner Preferences.

Partner preferences are an important differential in relationship formation and evolutionary fitness, and vary according to individual, ecological, and social factors. In this study, we evaluated the variation in preference for intelligence, kindness, physical attractiveness, health, and socioeconomic level among individuals of different sexes and sexual orientations in a Brazilian sample. We analyzed the preference scores of 778 heterosexual, bisexual, and homosexual men and women in three budgeted mate design tasks (low vs. medium vs. high budget) and their association with sociosexuality, attachment styles, homogamy, and willingness to engage in short- and long-term relationships. Results indicated a global trait preference order, with intelligence ranking first, followed by kindness, physical attractiveness, health, and lastly by socioeconomic status. Typical sex differences were observed mostly within the heterosexual group, and specific combinations of sex and sexual orientation were linked to variation in preference for physical attractiveness, kindness, and socioeconomic status. We also found unique associations of the other variables with partner preferences and with willingness to engage in short- or long-term relationships. By exploring the partner preferences of non-heterosexual individuals from a Latin American country, an underrepresented group in evolutionary psychology research, our results help understand the universal and specific factors that guide partner preferences and human sexual behavior.

Is the Bland-Altman plot method useful without inferences for accuracy, precision, and agreement?

OBJECTIVE: This study aims to propose a comprehensive alternative to the Bland-Altman plot method, addressing its limitations and providing a statistical framework for evaluating the equivalences of measurement techniques. This involves introducing an innovative three-step approach for assessing accuracy, precision, and agreement between techniques, which enhances objectivity in equivalence assessment. Additionally, the development of an R package that is easy to use enables researchers to efficiently analyze and interpret technique equivalences. METHODS: Inferential statistics support for equivalence between measurement techniques was proposed in three nested tests. These were based on structural regressions with the goal to assess the equivalence of structural means (accuracy), the equivalence of structural variances (precision), and concordance with the structural bisector line (agreement in measurements obtained from the same subject), using analytical methods and robust approach by bootstrapping. To promote better understanding, graphical outputs following Bland and Altman's principles were also implemented. RESULTS: The performance of this method was shown and confronted by five data sets from previously published articles that used Bland and Altman's method. One case demonstrated strict equivalence, three cases showed partial equivalence, and one showed poor equivalence. The developed R package containing open codes and data are available for free and with installation instructions at Harvard Dataverse at https://doi.org/10.7910/DVN/AGJPZH. CONCLUSION: Although easy to communicate, the widely cited and applied Bland and Altman plot method is often misinterpreted, since it lacks suitable inferential statistical support. Common alternatives, such as Pearson's correlation or ordinal least-square linear regression, also fail to locate the weakness of each measurement technique. It may be possible to test whether two techniques have full equivalence by preserving graphical communication, in accordance with Bland and Altman's principles, but also adding robust and suitable inferential statistics. Decomposing equivalence into three features (accuracy, precision, and agreement) helps to locate the sources of the problem when fixing a new technique.

Is the Bland-Altman plot method useful without inferences for accuracy, precision, and agreement?

ABSTRACT OBJECTIVE This study aims to propose a comprehensive alternative to the Bland-Altman plot method, addressing its limitations and providing a statistical framework for evaluating the equivalences of measurement techniques. This involves introducing an innovative three-step approach for assessing accuracy, precision, and agreement between techniques, which enhances objectivity in equivalence assessment. Additionally, the development of an R package that is easy to use enables researchers to efficiently analyze and interpret technique equivalences. METHODS Inferential statistics support for equivalence between measurement techniques was proposed in three nested tests. These were based on structural regressions with the goal to assess the equivalence of structural means (accuracy), the equivalence of structural variances (precision), and concordance with the structural bisector line (agreement in measurements obtained from the same subject), using analytical methods and robust approach by bootstrapping. To promote better understanding, graphical outputs following Bland and Altman's principles were also implemented. RESULTS The performance of this method was shown and confronted by five data sets from previously published articles that used Bland and Altman's method. One case demonstrated strict equivalence, three cases showed partial equivalence, and one showed poor equivalence. The developed R package containing open codes and data are available for free and with installation instructions at Harvard Dataverse at https://doi.org/10.7910/DVN/AGJPZH. CONCLUSION Although easy to communicate, the widely cited and applied Bland and Altman plot method is often misinterpreted, since it lacks suitable inferential statistical support. Common alternatives, such as Pearson's correlation or ordinal least-square linear regression, also fail to locate the weakness of each measurement technique. It may be possible to test whether two techniques have full equivalence by preserving graphical communication, in accordance with Bland and Altman's principles, but also adding robust and suitable inferential statistics. Decomposing equivalence into three features (accuracy, precision, and agreement) helps to locate the sources of the problem when fixing a new technique.

Modeling VI and VDRL feedback functions: Searching normative rules through computational simulation.

We present the mathematical description of feedback functions of variable interval and variable differential reinforcement of low rates as functions of schedule size only. These results were obtained using an R script named Beak, which was built to simulate rates of behavior interacting with simple schedules of reinforcement. Using Beak, we have simulated data that allow an assessment of different reinforcement feedback functions. This was made with unparalleled precision, as simulations provide huge samples of data and, more importantly, simulated behavior is not changed by the reinforcement it produces. Therefore, we can vary response rates systematically. We've compared different reinforcement feedback functions for random interval schedules, using the following criteria: meaning, precision, parsimony, and generality. Our results indicate that the best feedback function for the random interval schedule was published by Baum (1981). We also propose that the model used by Killeen (1975) is a viable feedback function for the random differential reinforcement of low rates schedule. We argue that Beak paves the way for greater understanding of schedules of reinforcement, addressing still open questions about quantitative features of simple schedules. Also, Beak could guide future experiments that use schedules as theoretical and methodological tools.

Rachlin's extended self: Influences on a Brazilian research group.

We pay tribute to Rachlin's work stating that researching and writing for posterity is an act of self-control and altruism. We show how Rachlin's work influenced a series of seminars at the University of São Paulo (Brazil) based on his book from 1989, Judgment, Decision, and Choice. This influence is illustrated through two empirical exercises conducted during our seminars, where students were actively involved in data collection and analysis. The first exercise is about judgment of randomness involving coin tossing. The second is a replication of a procedure by Jones and Rachlin (2006) about social discounting of monetary quantities. We use these empirical examples to highlight some of Rachlin's major contributions to the science of behavior and their implications to our seminars and to ourselves as researchers.

Better to be in agreement than in bad company : A critical analysis of many kappa-like tests.

We assessed several agreement coefficients applied in 2x2 contingency tables, which are commonly applied in research due to dichotomization. Here, we not only studied some specific estimators but also developed a general method for the study of any estimator candidate to be an agreement measurement. This method was developed in open-source R codes and it is available to the researchers. We tested this method by verifying the performance of several traditional estimators over all possible configurations with sizes ranging from 1 to 68 (total of 1,028,789 tables). Cohen's kappa showed handicapped behavior similar to Pearson's r, Yule's Q, and Yule's Y. Scott's pi, and Shankar and Bangdiwala's B seem to better assess situations of disagreement than agreement between raters. Krippendorff's alpha emulates, without any advantage, Scott's pi in cases with nominal variables and two raters. Dice's F1 and McNemar's chi-squared incompletely assess the information of the contingency table, showing the poorest performance among all. We concluded that Cohen's kappa is a measurement of association and McNemar's chi-squared assess neither association nor agreement; the only two authentic agreement estimators are Holley and Guilford's G and Gwet's AC1. The latter two estimators also showed the best performance over the range of table sizes and should be considered as the first choices for agreement measurement in contingency 2x2 tables. All procedures and data were implemented in R and are available to download from Harvard Dataverse https://doi.org/10.7910/DVN/HMYTCK.

Assessment of a digital game as a neuropsychological test for postoperative cognitive dysfunction.

OBJECTIVE: Postoperative cognitive dysfunction may result from worsening in a condition of previous impairment. It causes greater difficulty in recovery, longer hospital stays, and consequent delay in returning to work activities. Digital games have a potential neuromodulatory and rehabilitation effect. In this study, a digital game was used as a neuropsychological test to assess postoperative cognitive dysfunction, with preoperative patient performance as control. METHODS: It was a non-controlled study, with patients selected among candidates for elective non-cardiac surgery, evaluated in the pre- and postoperative periods. The digital game used has six phases developed to evaluate selective attention, alternating attention, visuoperception, inhibitory control, short-term memory, and long-term memory. The digital game takes about 25 minutes. Scores are the sum of correct answers in each cognitive domain. Statistical analysis compared these cognitive functions pre- and post-surgery using a generalized linear mixed model (ANCOVA). RESULTS: Sixty patients were evaluated, 40% male and 60% female, with a mean age of 52.7 ± 13.5 years. Except for visuoperception, a reduction in post-surgery scores was found in all phases of the digital game. CONCLUSION: The digital game was able to detect decline in several cognitive functions postoperatively. As its completion is faster than in conventional tests on paper, this digital game may be a potentially recommended tool for assessing patients, especially the elderly and in the early postoperative period.

Comparison of digital games as a cognitive function assessment tool for current standardized neuropsychological tests.

OBJECTIVE: Cognitive dysfunction may occur postoperatively. Fast and efficient assessment of Postoperative Cognitive Dysfunction (POCD) can minimize loss of quality of life, and therefore, a study comparing a digital game with standard neuropsychological tests to assess executive, mnemonic, and attention functions to evaluate POCD seems to be relevant both for research and clinical practice. METHODS: A battery of standardized tests and a digital game (MentalPlus®) were administered to 60 patients at the Central Institute of Hospital das Clínicas in São Paulo (36 women and 24 men), with ages between 29 and 82 years, pre- and post-surgery performed under anesthesia. Correlation and linear regression model were used to compare the scores obtained from the standardized tests to the scores of the six executive and cognitive functions evaluated by the game (short- and long-term memory, selective and alternating attention, inhibitory control, and visual perception). RESULTS: After correlation analysis, a statistically significant result was found mainly for the correlation between the scores from the phase of the digital game assessing the visuoperception function and the scores from the A and B cards of the Stroop Test (p < 0.001, r = 0.99 and r = 0.64, respectively), and the scores from TMTA (p = 0.0046, r = 0.51). We also found a moderate correlation between the phase of the game assessing short-memory function and VVLT (p < 0.001, r = 0.41). No statistically significant correlations were found for the other functions assessed. CONCLUSION: The digital game provided scores in agreement with standardized tests for evaluating visual perception and possibly short-term memory cognitive functions. Further studies are necessary to verify the correlation of other phases of the digital game with standardized tests assessing cognitive functions.

Application of a model based on fuzzy logic for evaluating nursing diagnostic accuracy of students.

PURPOSE: To describe a model for assessing nursing diagnostic accuracy and its application to undergraduate students, comparing students' performance according to the course year. METHODS: This model, based on the theory of fuzzy sets, guides a student through three steps: (a) the student must parameterize the model by establishing relationship values between defining characteristic/risk factors and nursing diagnoses; (b) presentation of a clinical case; (c) the student must define the presence of each defining characteristic/risk factors for the clinical case. Subsequently, the model computes the most plausible diagnoses by taking into account the values indicated by the student. This gives the student a performance score in comparison with parameters and diagnoses that were previously provided by nursing experts. These nursing experts collaborated with the construction of the model indicating the strength of the relationship between the concepts, meaning, they parameterized the model to compare the student's choice with the expert's choice (gold standard), thus generating performance scores for the student. The model was tested using three clinical cases presented to 38 students in their third and fourth years of the undergraduate nursing course. RESULTS: Third year students showed superior performance in identifying the presence of defining characteristic/risk factors, while fourth year students showed superior performance in the diagnoses by the model. CONCLUSIONS: The Model for Evaluation of Diagnostic Accuracy Based on Fuzzy Logic applied in this study is feasible and can be used to evaluate students' performance. In this regard, it will open a broad variety of applications for learning and nursing research. LIMITATIONS: Despite the ease in filling the printed questionnaires out, the number of steps and fields to fill in may explain the considerable number of questionnaires with incorrect or missing data. This was solved in the digital version of the questionnaire. In addition, in more complex cases, it is possible that an expert opinion can lead to a wrong decision due to the subjectivity of the diagnostic process.

Fuzzy cognitive map in differential diagnosis of alterations in urinary elimination: a nursing approach.

PURPOSE: To develop a decision support system to discriminate the diagnoses of alterations in urinary elimination, according to the nursing terminology of NANDA International (NANDA-I). METHODS: A fuzzy cognitive map (FCM) was structured considering six possible diagnoses: stress urinary incontinence, reflex urinary incontinence, urge urinary incontinence, functional urinary incontinence, total urinary incontinence and urinary retention; and 39 signals associated with them. The model was implemented in Microsoft Visual C++(®) Edition 2005 and applied in 195 real cases. Its performance was evaluated through the agreement test, comparing its results with the diagnoses determined by three experts (nurses). The sensitivity and specificity of the model were calculated considering the expert's opinion as a gold standard. In order to compute the Kappa's values we considered two situations, since more than one diagnosis was possible: the overestimation of the accordance in which the case was considered as concordant when at least one diagnoses was equal; and the underestimation of the accordance, in which the case was considered as discordant when at least one diagnosis was different. RESULTS: The overestimation of the accordance showed an excellent agreement (kappa=0.92, p<0.0001); and the underestimation provided a moderate agreement (kappa=0.42, p<0.0001). In general the FCM model showed high sensitivity and specificity, of 0.95 and 0.92, respectively, but provided a low specificity value in determining the diagnosis of urge urinary incontinence (0.43) and a low sensitivity value to total urinary incontinence (0.42). CONCLUSIONS: The decision support system developed presented a good performance compared to other types of expert systems for differential diagnosis of alterations in urinary elimination. Since there are few similar studies in the literature, we are convinced of the importance of investing in this kind of modeling, both from the theoretical and from the health applied points of view. LIMITATIONS: In spite of the good results, the FCM should be improved to identify the diagnoses of urge urinary incontinence and total urinary incontinence.

Software application that evaluates the diagnostic accuracy of nursing students.

PURPOSE: Apply the educational software Fuzzy Kitten with undergraduate Brazilian nursing students. METHODS: This software, based on fuzzy logic, generates performance scores that evaluate the ability to identify defining characteristics/risk factors present in clinical cases, relate them with nursing diagnoses, and determine the diagnoses freely or using a decision support model. FINDINGS: There were differences in student performance compared to the year of the course. The time to perform the activity did not present a significant relation to the performance. The students' scores in the diagnoses indicated by the model was superior (p= .01). CONCLUSIONS: The software was able to evaluate the diagnostic accuracy of students. IMPLICATIONS: The software enables an objective evaluation of diagnostic accuracy.

[The development and evaluation of software to verify diagnostic accuracy]. / Desenvolvimento e avaliação de um software que verifica a acurácia diagnóstica.

This article describes the development and evaluation of software that verifies the accuracy of diagnoses made by nursing students. The software was based on a model that uses fuzzy logic concepts, including PERL, the MySQL database for Internet accessibility, and the NANDA-I 2007-2008 classification system. The software was evaluated in terms of its technical quality and usability through specific instruments. The activity proposed in the software involves four stages in which students establish the relationship values between nursing diagnoses, defining characteristics/risk factors and clinical cases. The relationship values determined by students are compared to those of specialists, generating performance scores for the students. In the evaluation, the software demonstrated satisfactory outcomes regarding the technical quality and, according to the students, helped in their learning and may become an educational tool to teach the process of nursing diagnosis.

Desenvolvimento e avaliação de um software que verifica a acurácia diagnóstica / The development and evaluation of software to verify diagnostic accuracy / Desarrollo y evaluación de un software que verifica la exactitud diagnóstica

Este artigo descreve o desenvolvimento e avaliação de um software que verifica a acurácia diagnóstica de alunos de enfermagem. O software foi baseado num modelo que utiliza conceitos da lógica fuzzy, em PERL, banco de dados MySQL para acesso pela internet e a classificação NANDA-I 2007-2008. Avaliou-se a qualidade técnica e a usabilidade do software utilizando instrumentos específicos. A atividade proposta no software possui quatro etapas nas quais o aluno estabelece valores de relação entre diagnósticos de enfermagem, características definidoras/fatores de risco e casos clínicos. Os valores de relação determinados pelo aluno são comparados aos de especialistas, gerando escores de desempenho para o aluno. Na avaliação, o software atendeu satisfatoriamente as necessidades de qualidade técnica e, segundo os alunos, trouxe benefícios ao aprendizado, podendo transformar-se em uma ferramenta educacional no ensino do diagnóstico de enfermagem.

This article describes the development and evaluation of software that verifies the accuracy of diagnoses made by nursing students. The software was based on a model that uses fuzzy logic concepts, including PERL, the MySQL database for Internet accessibility, and the NANDA-I 2007-2008 classification system. The software was evaluated in terms of its technical quality and usability through specific instruments. The activity proposed in the software involves four stages in which students establish the relationship values between nursing diagnoses, defining characteristics/risk factors and clinical cases. The relationship values determined by students are compared to those of specialists, generating performance scores for the students. In the evaluation, the software demonstrated satisfactory outcomes regarding the technical quality and, according to the students, helped in their learning and may become an educational tool to teach the process of nursing diagnosis.

Este artículo describe el desarrollo y evaluación de un software que verifica la exactitud diagnóstica de alumnos de enfermería. El software se basó en un modelo que utiliza conceptos de lógica fuzzy, en PERL, banco de datos MySQL para acceso por Internet y la clasificación NANDA-I 2007-2008. Se evaluó calidad técnica y usabilidad del software utilizando instrumentos específicos. La actividad propuesta en el software consiste en cuatro etapas, en las que el alumno establece valores de relación entre diagnósticos de enfermería, características de definición/factores de riesgo y casos clínicos. Los valores de relación determinados por el alumno son comparados con los de especialistas, generando puntajes de desempeño del alumno. En la evaluación, el software atendió satisfactoriamente las necesidades de calidad técnica y mostró que, en la percepción de los alumnos, trajo beneficios de aprendizaje, pudiendo transformarse en una herramienta educativa en la enseñanza del diagnóstico de enfermería.

Migramed II - Educação e saúde: condicionantes estruturais e institucionais da atração e fixação de médicos em território nacional / Migramed II - Education and health: structural and institutional constraints of attraction and fixation of physicians in national territory

INTRODUÇÃO: A partir dos resultados do MigraMed I, evidenciou-se a necessidade de aprofundar as análises dos movimentos migratórios, com o intuito de contribuir positivamente nos processos de formulação de políticas capazes de minimizar as desigualdades regionais. Assim, a migração de médicos e outros profissionais de saúde; a oferta diferenciada de capacitação; a integração entre ensino e serviços; o evolver da regionalização no território nacional; as condições e a qualidade da atenção à saúde são dimensões que carecem de explicações estruturais relacionadas com os níveis de desenvolvimento humano, social e dos serviços de saúde das diferentes localidades. OBJETIVOS: Os objetivos específicos: 1- revisão dos bancos de dados da CNRM e CFM; 2- descrição do perfil da população médica, analisando as variáveis - gênero, local de formação; local de atividade 3- descrição e quantificação dos processos migratórios de médicos 4- caracterização dos principais fluxos e movimentos migratórios dos médicos, considerando os momentos de graduação e da residência Médica. MATERIAL E MÉTODOS: Trata-se de pesquisa descritiva, retrospectiva de base quantitativa, com dados de fontes secundárias. Para a execução deste projeto, o ObservaRHSP em conjunto com membros do Departamento de Informática Médica da FMUSP, estabeleceram uma parceria com o Conselho Federal de Medicina (CFM) e o Conselho Regional de Medicina do Estado de São Paulo (CREMESP), que disponibilizaram seus bancos de dados dos registros dos médicos, e com a Comissão Nacional de Residência Médica referentes aos títulos de especialistas. RESULTADOS: A opção metodológica de realizar os recortes dos fluxos migratórios por década de profissionais formados, e não exatamente por momento da migração, apresenta um viés a ser considerado, qual seja o de distribuir em momentos distintos e aparentemente regulares o que pode estar ocorrendo em momentos concomitantes e interconectados. Tal opção se deu em função da limitação para discriminar adequadamente nos registros dos bancos de dados os movimentos migratórios intermediários dos profissionais, o que deve vir a ser melhorado com a revisão dos bancos pelas respectivas entidades. CONCLUSÃO: Tal estudo ganha particular interesse considerando-se que foi possível identificar mudanças de fluxos entre as décadas analisadas. Este fato talvez permita uma melhor caracterização não apenas sobre o que determina, ou orienta este movimentos, mas principalmente quando e em que intensidade estes fatores passam a exercer influência a ponto de redirecionar tais movimentos.

Aging is not senescence: a short computer demonstration and implications for medical practice.

INTRODUCTION: The discussion regarding the evolution of aging is almost as old as Darwinian Evolution Theory, but to date, it has remained one of biology's unresolved problems. One issue is how to reconcile natural selection, which is understood as a process that purges deleterious characteristics, with senescence, which seems to offer no advantages to the individual. METHOD: A computer simulation that illustrates an evolutionary mechanism for the development of senescence in populations is presented. DISCUSSION: In this article, we debate that two popular explanations for the existence of senescence, namely, (1) the removal of elders for the benefit of the species and (2) the progressive deterioration of the organic machine due to continuous use, are not correct. While human populations continue to age, it is important that the physician understands that senescence, here defined as the progressive impairment of an organism, does not necessarily accompany aging, which we here define as the mere passage of time. As such, we argue that certain processes that were originally assumed to be part of aging should have their status changed because they are actually diseases. Physicians often encounter situations that depend on a better understanding of what limitations senescence imposes on most living species. The concepts of aging (the unavoidable passage of time), senescence (progressive physiologic impairment), and senility (the pathological development of diseases), are discussed.

Aging is not senescence: a short computer demonstration and implications for medical practice

INTRODUCTION: The discussion regarding the evolution of aging is almost as old as Darwinian Evolution Theory, but to date, it has remained one of biology's unresolved problems. One issue is how to reconcile natural selection, which is understood as a process that purges deleterious characteristics, with senescence, which seems to offer no advantages to the individual. METHOD: A computer simulation that illustrates an evolutionary mechanism for the development of senescence in populations is presented. DISCUSSION: In this article, we debate that two popular explanations for the existence of senescence, namely, (1) the removal of elders for the benefit of the species and (2) the progressive deterioration of the organic machine due to continuous use, are not correct. While human populations continue to age, it is important that the physician understands that senescence, here defined as the progressive impairment of an organism, does not necessarily accompany aging, which we here define as the mere passage of time. As such, we argue that certain processes that were originally assumed to be part of aging should have their status changed because they are actually diseases. Physicians often encounter situations that depend on a better understanding of what limitations senescence imposes on most living species. The concepts of aging (the unavoidable passage of time), senescence (progressive physiologic impairment), and senility (the pathological development of diseases), are discussed.

Protecting patient privacy by quantifiable control of disclosures in disseminated databases.

One of the fundamental rights of patients is to have their privacy protected by health care organizations, so that information that can be used to identify a particular individual is not used to reveal sensitive patient data such as diagnoses, reasons for ordering tests, test results, etc. A common practice is to remove sensitive data from databases that are disseminated to the public, but this can make the disseminated database useless for important public health purposes. If the degree of anonymity of a disseminated data set could be measured, it would be possible to design algorithms that can assure that the desired level of confidentiality is achieved. Privacy protection in disseminated databases can be facilitated by the use of special ambiguation algorithms. Most of these algorithms are aimed at making one individual indistinguishable from one or more of his peers. However, even in databases considered "anonymous", it may still be possible to obtain sensitive information about some individuals or groups of individuals with the use of pattern recognition algorithms. In this article, we study the problem of determining the degree of ambiguation in disseminated databases and discuss its implications in the development and testing of "anonymization" algorithms.