Test-retest Repeatability; Integrated assessment of adherence to treatment questionnaire for Cardiometabolic Diseases

J Atherosclerosis Prev Treat. 2023 Jan-Apr;14(1):11-22 | doi:10.53590/japt.02.1043


Vasiliki Belitsi1, Thomas Tsiampalis1,2, Vasiliki Kalantzi1, Odysseas Androutsos1, Fotini Bonoti1, Demosthenes B. Panagiotakos2,3, Rena I. Kosti1

1Department of Nutrition and Dietetics, School of Physical Education, Sports and Dietetics, University of Thessaly, Trikala, Greece
2Department of Nutrition and Dietetics, School of Health Science and Education, Harokopio University, Athens, Greece
3Faculty of Health, University of Canberra, Canberra, Australia



Aim: Low adherence to health-related behaviors to treatment is still a major public health challenge in primary healthcare settings. Our aim was to assess the repeatability of a tool that can be used by health care professionals in the primary health care sector, as a means to evaluate the degree of adherence to medication and recommended lifestyle changes of patients with cardiometabolic diseases while simultaneously identifying potential treatment obstacles.

Material: The Integrated Assessment of Adherence to Treatment Questionnaire for Cardio Metabolic Diseases (IAATQ-CMD) tool includes 126 questions concerning the following domains: (i) socio-demographic characteristics, (ii) medical history, (iii) dietary and lifestyle habits, (iv) healthcare system, (v) patients’ disease/treatment/health status awareness, (vi) adherence to medication (vii) self-efficacy to medication and lifestyle changes, and (viii) therapeutic treatment views/perceptions. In order to evaluate the repeatability of the IAATQ- CMD tool, Cohen’s kappa statistic was calculated for qualitative questions, while Kendall’s tau-b and the Bland & Altman methods were applied for quantitative questions.

Results: Fifty individuals (Mean (Standard Deviation (SD)): (66 (14) years old; 68% females) were recruited for the repeatability process. The repeatability of all parts of the IAATQ-CMD questionnaire was found to be adequate, as the relevant statistics (Cohen’s kappa, Kendall’s tau-b and the Bland & Altman method) ranged in acceptable limits.

Key words: Diet, medication, adherence, questionnaire, health behavior

Corresponding author: Associate Professor Rena I. Kosti, Department of Nutrition and Dietetics, School of Physical Education, Sports and Dietetics, University of Thessaly, Trikala, Greece, Argonafton 1Γ, Trikala 421 32, Tel. +30 2431 023602, E-mail: renakosti@uth.gr

Submission: 20.12.2022, Acceptance: 22.01.2023


According to the European Society of Preventive Medicine (ESPREVMED), it is projected that by 2030 the deaths from cardiovascular diseases (CVDs) will reach the tremendous number of 23.3 million, keeping CVDs as the leading cause of death globally.1  Medication adherence, which according to the World Health Organization (WHO) is defined as “the degree to which the person’s behavior corresponds with the agreed recommendations from a health care provider”,2 still remains a crucial problem for CVD patients.3 Poor medication adherence leads to poor clinical outcomes, such as re-hospitalization, increased mortality, 3,4 and subsequent serious public health implications.5 According to the literature almost half of CVD patients are poor adherers to prescribed medications,6,7 and therefore healthcare professionals need to utilize multiple approaches, design effective health interventions and identify simple solutions, in order to improve and maintain their patients’ short and long-term medication adherence levels.8,9

On top of that, the majority of CVDs could be preventable through the adoption of healthy behavioral habits (i.e., tobacco cessation, healthy dietary habits, loss of weight, physical activity, and moderate use of alcohol). According to a recently conducted microsimulation study in Greece, it was shown that improving the adherence level to the Mediterranean diet in at least 10% of the population, could lead to a significant reduction in 10-year CVD onset, recurrence, and mortality.10 However, on a global level the overall “ideal cardiovascular health”  through the adoption of healthy lifestyle remains well below optimal levels.11 It is therefore obvious that the combined synergistic effect of adherence to both medication and healthy lifestyle habits is a one-way approach to combat the burden of CVD in primary health care settings in an efficient and effective manner. However, there is scarce evidence regarding the development of tools encompassing all related to adherence axes using the WHO conceptual framework accounting for their interaction in a rather multi-dimensional and integrated approach.12,13

Therefore, the present study aims to develop for the first time and test the repeatability of the Integrated Assessment of Adherence to Treatment Questionnaire in Cardio Metabolic Diseases (IAATQ-CMD), a new patient-based tool that can be used in primary health care settings, and can evaluate the degree of adherence to medication and healthy lifestyle habits in patients with cardiometabolic risk factors while concomitantly identifying the key treatment obstacles, taking into consideration the reported cultural diversity among different populations.14


Questionnaire development

The development of the IAATQ-CMD was based on the following five pylons: (I) the multidimensional conceptual model developed by WHO12 referring to the five-dimensional domains affecting medication adherence; (II) the American Heart Association’s (AHA) recommended rapid diet screener tools15; (III) existing validated scales estimating the level of medication adherence and/ or medication self –efficacy16-24; (IV) the clinical practice guidelines on the primary prevention of CVDs25,26; and (V) the published literature concerning the beliefs, perceptions, and  self-efficacy related to adherence both to medication and to recommended health behavior modifications.27-30

On the basis of this information, we developed a conceptual draft to guide the development of the preliminary versions of the IAATQ-CMD consisting of five core content domains: (i) sociodemographic factors, (ii) disease-related factors, (iii) treatment-related factors including medication and lifestyle habits, (iv) health care system factors, as well as (v) self –efficacy/perceptions/awareness/social factors. We then generated questionnaire items for all content domains guided by: literature findings per domain as regards the potential reasons for non-adherence to treatment in cardiometabolic diseases 27,29; literature findings relevant to recommended healthy lifestyle habits and behaviors 25,26; borrowed specific items and/or validated scales from existing questionnaires 16,24 following the approval of the corresponding authors. Some items were specifically customized to cardiometabolic patients, cultural characteristics as well as the culinary habits of the Mediterranean region.

We pre-tested the preliminary version of the IAATQ-CMD through face-to-face interviews with 10 health care professionals in primary care settings (health visitors, general practitioners, internal medicine doctors, cardiologists, sociologists and psychologists) in order to evaluate content validity, clarity and appropriateness of wording, item sequence as well as completeness and integrity of items. Minor modifications were made to the pre-test questionnaires to produce field test versions of the IAATQ-CMD as regards questionnaire format in Google forms, instructions of use and consent in accordance to General Data Protection Regulation (GDPR).

Ethic approval and consent to participate 

The study was implemented in accordance with the ethical standards of the University of Thessaly Ethics Committee (Ethics 11-14/07/2022) and with the Declaration of Helsinki (1989). All patients were informed on the confidentiality, aims and procedures of the study.

Structure and content of the Questionnaire

Elements of seven (7) questionnaires were included in the final version of the IAATQ-CMD. These include the r-MEDAS questionnaire 21,23 (12 questions), the MedDiet Score 18 (8 questions), the Morisky Medication Adherence Scale MMAS-4 and MMAS-8 16,20 (5 questions), the Self-Efficacy for Appropriate Medication Use Scale SEAMS 19  (6 questions), MASES-R 24 (7 questions) and the Hill-Bone Scale 17(4 questions). It is noted that several questions were common in the above-mentioned questionnaires, while the remaining questions were formulated based on literature findings. Nevertheless, permission was requested and granted by all authors whose questionnaires are used in a solid, partial or modified way for the purposes of our research. The questionnaire consists of total 126 questions spread in eight (8) subsections having different type of response formats as follows:

Socio-Demographic Characteristics (9 questions)

Age, weight and height were self-reported. This section also includes questions related to educational level, professional and marital status, as well as family/ personal income.

Medical history (17 questions)

The medical history, count and frequency of patients’ pills intake per disease and total years of suffering since the diagnosis are also included. The diseases investigated are hypertension, type II diabetes, type I diabetes, hypercholesterolemia, elevated triglycerides, obesity, coronary heart disease, stroke, fatty liver (non-alcoholic fatty liver disease). There also exists a question on whether patients suffer from any other diseases (comorbidities) with the form of YES/NO. If YES the principle investigator records the answer in the last section.

Dietary and Lifestyle Assessment (56 questions)

This section incorporates questions related to dietary by including all major food groups and lifestyle habits. The frequency of consumption ranged from “Never”, “≤ 1”, “1-2”, “2-3”, “3-4”, “5-6”, “> 6”, or “Never”, “1”, “2”, “3”, “4”, “> 4”, “Daily”, and “Yes/No” depending on whether the question measures serving frequency or habits of consumption. New questions were also created in order to incorporate consumption habits of Greek traditional dishes as well as lifestyle habits such as physical activity (frequency, duration, type of exercise), smoking habits (yes/no, duration), sedentary behavior, sleep (hours), weight control (yes/no) and social life (dinning out with friends).

Dietary habits in terms of the overall consumption of fruits, vegetables, lean and red meat, fish, dairy, legumes, salt, sugar and alcohol among others are being recorded. More specific questions regarding alcohol consumption are included (type of alcoholic beverage and drinking pattern). Pictures from the Greek “National Dietary Guidelines for Adults” were used as reference portion guide in order to best describe food portions, ensuring comprehension and avoid discrepancies.

Health care system (3 questions)

Likert scale questions in the form  of  “Satisfactory”, “Moderate”, “Inadequate” are used in order for the participants to be able to rate the Primary Health Care System in Greece based on their experience in terms of  the availability of healthcare professionals, time devoted during the visit and ease of access.

Adherence to medication (11 questions)

Likert scale questions in the form of “Never”, “Sometimes” “Most times”, “Always” or (Yes/No) are used in order for the participants to be able to express the reasons of non-adherence to medication.

Awareness of disease, therapeutic treatment and health status (5 questions)

Patients’ awareness as regards to the severity of their symptoms, the long term life implications of their disease, the clarity of the recommendations (both in terms of medication and lifestyle changes) received by the healthcare professionals relevant to their treatment, are asked with the form of YES/NO as well for their health status in the form of Likert scale questions (“Excellent”, “Very Good”, “Good”, “Medium”, “Poor”).

Evaluation of Self-efficacy to Medication and Lifestyle Adherence (15 questions)

Self-efficacy is evaluated through questions by the use of Likert Scale. Questions in the form of “I am not confident”, “I am confident”, “I am very confident” are used to evaluate participants’ confidence in their ability to take their medications. Questions in the form of “Not at all”, “A little bit”, “Moderately”, “Enough”, “Very” are used for the evaluation of patients’ self-efficacy to healthy life style changes (i.e. alcohol consumption, physical activity, smoking habits and diet).

Therapeutic treatment Views/Perceptions (10 questions)

Likert scale questions in the form of “Agree”, “I am not sure”, “Disagree” are used to assess patients views, and perceptions on drugs (polypharmacy, toxicity, necessity, importance, substitution with other traditional “remedies”), as well as the significance of lifestyle changes for the management of their disease.

Test and Re-test repeatability
Patient Selection and Recruitment

Patients who visit Primary Health Care settings were recruited from the primary health care units of the metropolitan area of Athens. Inclusion criteria were Greek nationality, being at least 18 years of age, suffering from at least one of the following diseases: hypertension, type II diabetes, type I diabetes, hypercholesterolemia, elevated triglycerides, obesity, coronary heart disease, stroke, fatty liver (non-alcoholic fatty liver disease) and taking medication for their relevant condition for at least a year. Patients with psychiatric disorders such as schizophrenia, bipolar disease or dementia were excluded.

Following the approval from the ethics committee of the University of Thessaly, patients were sent informed consent forms, information sheets, and questionnaires by e-mail. More specifically, the IAATQ-CMD questionnaire was sent via e-mail and was completed on line.  A trained investigator was virtually present throughout the whole procedure of completing the questionnaire to address any potential misconceptions. The completion of the questionnaire lasted on average 16 min. Fifty participants, who were randomly selected through the medical registry of the central metropolitan primary health care unit (aged Mean (Standard Deviation (SD)): 66 (14) years) completed the IAATQ-CMD twice with an interval of 2 weeks, for test-retest reliability.

Statistical Analysis

Demographic and clinical characteristics are presented in terms of Mean (Standard Deviation (SD)) values and absolute (N) and relative (%) frequencies, in case of continuous and categorical characteristics respectively. To evaluate the repeatability of the questionnaire related to the participants’ nutritional habits, Spearman’s rho and the Kendall’s tau-b coefficients31,32 were calculated from the information provided by the two administrations. Furthermore, to further evaluate the results for the agreement between the two administrations the Wilcoxon signed-rank test for the difference (bias) in intake, as well as the Bland & Altman method of agreement,33 were also applied. With respect to the Bland & Altman method the limits of agreement were calculated as mean(difference) ±1.96 standard deviation(difference), assuming normal distribution of the differences. Normality was tested using Q-Q plots. As for the rest aspects of the questionnaire, due to their categorical nature, the Cohen’s kappa coefficient of agreement was calculated, the interpretation of which is34 : values ≤ 0 as indicating no agreement and 0.01–0.20 as none to slight, 0.21–0.40 as fair, 0.41– 0.60 as moderate, 0.61–0.80 as substantial, and 0.81–1.00 as almost perfect agreement. All statistical analyses were performed in STATA version 17.


Sample characteristics

Regarding the sample characteristics, as depicted in Table 1, all participants were Greek, the majority of whom were females (68%) and their mean (SD) age was equal to 66 (14) years old. As for their educational level, 34% of the participants were at least of undergraduate level, while as regards their occupational status, 64% of the participants were retired and 30% of them were working either as state/ private employees, or as freelancers. Finally, the yearly personal/ family income of the 48% of the participants was at least equal to 18,000€. As for their clinical characteristics, the most frequently diagnosed disease was hypertension (68%), followed by hypercholesterolemia (56%) and diabetes mellitus II (44%), while only 2 participants were diagnosed with diabetes mellitus I, kidney disease and stroke.

Repeatability of the questionnaire related to nutrition

Food groups’ comparison suggested that the sub-questionnaire related to nutrition was repeatable for all of them, as there were no significant differences in the consumption of the food groups between the two phases. Moreover, Kendall’s tau-b ranged from 0.807 for “potatoes” to 0.993 for “soft drinks”. Similar results were found using the Spearman’s rho coefficient, with its values being a little bit higher compared to the respective values of the Kendall’s tau- b. The Bland & Altman method revealed acceptable mean differences and limits of agreement (Table 2).

Repeatability of the questionnaire related to lifestyle

As regards to the agreement in the questions related to the lifestyle characteristics of the participants, depicted in Table 3, Cohen’s kappa ranged between 0.802 and 1 for all the questions, except for beer consumption, suggesting that the agreement between the two phases was perfect. Regarding beer consumption, Cohen’s kappa was found to be equal to 0.769, suggesting a substantial agreement between the two recordings.

Repeatability of the questionnaire related to primary healthcare system, treatment of patients and factors related to their disease status and treatment

As depicted in Table 4, the agreement between the two phases was perfect in all cases (Cohen’s kappa> 0.8), except for the questions: “Do you consider the ability to access primary care centers to be satisfactory?” (Cohen’s kappa= 0.775), “Physician’s guidelines for lifestyle changes due to health status” (Cohen’s kappa= 0.658) and “How often do you miss scheduled appointments?” (Cohen’s kappa= 0.697), where the Cohen’s kappa statistic revealed a substantial agreement, as well.

Repeatability of the questionnaire related to the participants’ abilities to take their medication and to keep up with the changes in their lifestyle habits, as well as their views/perceptions for the therapeutic treatment

As regards to the participants’ abilities to take their medication (Table 5), the vast majority stated that they have the ability to take their medication even in cases when they feel frustrated, or no one reminds them. As for the agreement between the two phases, based on the Cohen’s kappa statistic (all values> 0.625), there was a substantial level of agreement between the two phases of the study. Regarding their ability to keep up with the changes in their lifestyle habits, in all cases at least 68% of the participants stated that they can keep up with these changes, while the agreement between the two phases was substantial in all questions (all Cohen’s kappa statistics> 0.723). Finally, when it comes to the participants’ opinion about their medication, the vast majority of them supported the medication’s usefulness, as just 1 participant agreed that the negative effects of drugs outweigh the positive ones, while at least 9 out of 10 participants supported that both the use of drugs and lifestyle changes are necessary for the effective treatment of a disease. Finally, the agreement between the two phases, was perfect in all questions, as the Cohen’s kappa statistic ranged between 0.732 and 1.


Data analysis revealed good repeatability of all parts of the IAATQ-CMD questionnaire. In particular, Kendall’s tau-b, in case of the questions related to the nutritional habits of the patients, as well as the Cohen’s kappa coefficient in all other cases, demonstrated excellent degree of agreement, for the repeatability of the IAATQ-CMD questionnaire. Furthermore, the Bland & Altman method also revealed acceptable mean differences and limits of agreement between the two phases of the questionnaire administration. It should also be noted that based on the Wilcoxon signed-rank test, a method that has been already used in various validation studies,35 there were no significant differences in the median intake of the various food groups.

According to the relevant literature, the level of adherence to CVD medication has been proposed to be assessed using self-report tools such as MMAS-4 MMAS-8, SEAMS, HBCS which are practical in daily routine examinations, have low cost, and are easy to administrate.36 However, AHA suggests the use of rapid diet screener tools in the primary care sector, designed to facilitate clinical decision-making for actionable health behavior modifications, such as the Mediterranean Diet Adherence Screener although new tools (MEDAS).15

The lack of consistent treatment adherence of patients is an additional cause of frustration in health care providers due to the time constraints that they face.3 Moreover literature findings suggest that unintentional non-adherence such as forgetfulness or carelessness may be rooted on medication perceptions, sociodemographic characteristics and type of chronic disease.37

Thus, given that adherence has been proven to be associated beyond disease and therapy factors, with healthcare, patient and social factors (in accordance to the Multidimensional Model proposed by the World Health Organization12 the simultaneous identification of patients’ views/perceptions for the therapeutic treatment as well as their self-efficacy toward healthy lifestyle behaviors is equally important for actionable interventions.


The IAATQ-CMD questionnaire is the first of its kind that incorporates all elements necessary for the overall evaluation of adherence to medication and necessary lifestyle behaviours of patients with cardiometabolic diseases in primary health care settings, while simultaneously allowing the health care professional to identify potential treatment barriers for actionable interventions.  Overall, the IAATQ-CMD tool could be considered a quick screening tool taking on average 16 min for completion and can be used both for assessing patients’ adherence to medication and lifestyle changes for actionable interventions in clinical practice as well as for research purposes. The early identification of potential barriers to treatment by health care providers could shed light on the distinction between patients’ intentional and unintentional non-adherence to treatment related behaviors. The proactive identification and corresponding management of patients’ unhealthy unintentional behaviours resulting from their wrong views and perceptions before they become an intentional pattern, could decrease the burden of cardiometabolic diseases.


Non declared

Conflicts of Interest

Non declared


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