Italian Version of the Laval Questionnaire: Validity and Reliability

Abstract

Background and Scope:

Morbid obesity is complicated by the presence of depression and poor quality of life. Bariatric surgery aims at improving quality of life of obese persons, as well as reducing mortality and medical risk factors. Quality of life assessment is important in clinical care planning, as well as in the evaluation of surgical outcomes. The Laval questionnaire has been specifically developed for patients with morbid obesity, but has never been validated into Italian; we aimed to produce an Italian version, in a population of patients scheduled for bariatric surgery.

Methods:

We conducted a multicenter observational study on a nonrandomized sample of patients (age 19–65 years), with morbid obesity and body mass index (BMI) ≥35, candidates for bariatric surgery (gastric banding or gastric bypass). Cronbach's alpha and factor analysis were used to assess internal consistency and structure.

Results:

One hundred sixty-three patients were enrolled, mean BMI of 42.8 ± 7.5 kg/m² (range 31–70). Excellent consistency (alpha >0.90) and concurrent validity with the Obesity-related Well Being Scale (ORWELL's) questionnaire (ρ = −0.78, p < 0.001). Factor analysis confirmed the six domains of the scale, all with good factor loadings (>0.75).

Conclusion:

In conclusion, we can state that the Italian version of the Laval questionnaire is valid and reliable for assessing quality of life in patients waiting for bariatric surgery.

Background

Since the 1970s, the increase in chronic diseases' incidence rates has been leading to the awareness that rarely are they curable¹; for this reason, attention has been shifting from “quantity” of life, expressed in terms of longevity, to quality of life.² In 1995, the World Health Organization defined quality of life as the “individuals' perception of their position in life in the context of culture and value systems in which they live, and in relation to their goals, expectations, standards and concerns”³; therefore, it is a dynamic, complex, and highly subjective concept, with both positive and negative aspects and includes physical, psychological, and social dimensions, expression of one's health.⁴

Obesity, the main chronic emerging disease in the last decades,⁵ is a complex multifactorial condition that can be related to emotional, environmental, and genetic situations; it is defined by the presence of a body mass index (BMI) greater than 30 kg/m².^6–8 Morbid obesity is often complicated by the presence of depression and compromised quality of life.^7,8 The decrease in the perception of health-related quality of life is especially evident in those patients with obesity who seek to undergo surgical treatment for weight loss.^9,10 Bariatric surgery is aimed at improving quality of life of persons with obesity, as well as reducing mortality and medical risk factors¹¹ Quality-of-life assessment in patients with obesity is important in clinical care planning, as well as in the evaluation of surgical outcomes. A number of generic tools for assessing quality of life have been developed and validated in literature to perform the assessment in clinical setting. Nevertheless, the researchers of the Laval Hospital, in Canada, pointed out a need for a specific questionnaire for patients with morbid obesity to assess the results of gastric banding and gastric bypass; therefore, they created a tool sensitive to changes induced by the treatment, specifically developed for patients with morbid obesity, which can be useful in both research and clinical practice.⁸ The Laval questionnaire has never been validated into Italian; the aim of this study is to produce and test an Italian version of such tool, in a population of Italian patients with obesity scheduled for bariatric surgery.

Materials and Methods

This multicenter validation study was conducted in Italian, in the years 2013 and 2014, at the Fondazione IRCCS Ospedale Maggiore Policlinico of Milan and the Casa di Cura San Pio X in Milan, two Italian centers of bariatric surgery. We included in the study, patients aged between 19 and 65 years, with morbid obesity and BMI ≥35, candidates for bariatric surgery (gastric banding or gastric bypass) in accordance with the international guidelines, and waiting for it. They were included if provided the informed consent. The presence of comorbidity was not a criterion for exclusion from the study. They were instead excluded patients with impaired cognitive status or not candidates for bariatric surgery. Patient recruitment occurred during the first visit with the bariatric surgeon: in that moment, the first administration of the tools took place (Time 0).

Validation study

Initially (Time 0) the Laval Questionnaire and four other validated instruments were administered to all patients.

The Laval Questionnaire, originally developed in Canada and written in French, includes 44 items divided into six domains: Symptoms; Activity/mobility; Personal hygiene/clothing; Emotions; Social interaction; and Sexual life. Each domain is scored on a 7-point Likert scale, higher scores meaning better quality of life. Patients are asked to indicate how their obesity has affected their lives in the last 4 weeks. The administration takes on average 10 min.⁸ In this study, we used the Italian version, created on the basis of a process of back-translation.

The Short Form (SF)-36 is a self-administered questionnaire¹² aimed at assessing eight physical and psychological domains. For each of the domains, the scores are linearly transformed into a scale from 0 to 100. Higher scores indicate better quality of life.^13,14 The eight-subscale form generates two general health summaries: the physical and mental component scores.^13,14 For all these items, subjects are required to respond considering their experience in the previous 4 weeks.¹⁵ The SF-36 questionnaire has adequate psychometric properties, including good construct validity, high internal consistency, and high test–retest stability.¹²

The Obesity-Related Well-Being is a self-reported measure of quality of life related to obesity. This tool has been developed with contributions of several health professionals who were asked to describe the most frequent and relevant complaints of obese patients recorded in daily clinical practice, and also with contributions of obese people who were asked to describe the effects of being overweight in their everyday life and indicate the most distressing physical and psychological symptoms.¹⁶ The questionnaire consists of 18 items, each of which is divided into two questions: the first is related to the importance (occurrence) that the person attaches to a symptom and the second refers to the importance of subjective impairment of physical or mental well-being experienced by the person in his personal life (relevance). The items are conceptually divided into three different areas: symptoms, discomfort, and impact. The total score is obtained from the sum of the scores of the individual items, calculated as the product of occurrence and relevance. Higher scores indicate a worse quality of life.^16–19

The Beck Depression Inventory is a tool composed by 21 items, which was developed specifically to identify depression. It was used as an assessment tool to monitor response to therapy in clinical trials and is the most widely used measure for the assessment of depressive symptoms in the context of bariatric surgery. The scores can range from 0 to 63 with a higher score representing a greater impairment of the symptoms of depression.^8,20

The Rosenberg Self-Esteem Scale is based on a phenomenological conception of self-esteem²¹: it is a widely used scale, is constituted of 10 items that relate to self-respect and self-acceptance, and requiring a response on a 4-point Likert scale.^15,21 Five items are positively worded and five negatively.²¹

After 2 weeks (Time 1), considering the stability from the clinical point of view in this time period and before any intervention, we proceeded to a second administration of all selected instruments, to evaluate the test–retest reliability of the Laval Questionnaire. The subjects remained unaware of the answers given in the previous compilation.

Statistical analysis

Cronbach's alpha coefficient was calculated to assess internal consistency. Factor analysis with nonorthogonal Promax rotation was used to verify the structure of the six subscales included in the original version of the questionnaire. Steven's criterion was used to retain relevant factors after rotation. Before conducting factor analysis, Kaiser-Meyer-Olkin's measure of sample adequacy was calculated and Bartlett's test of sphericity was performed. Test–retest stability was assessed by Wilcoxon's signed-rank test for paired data. Inter-rater reliability was not assessed, as the Laval questionnaire is meant to be self-administered. The level of significance for all tests was set at 0.05. All calculations were performed with SAS 9 for Windows (SAS, Inc., Cary, NY).

Results

One hundred sixty-three patients were enrolled, according to the inclusion criteria (36 males, 127 females), aged 43 ± 12, with mean BMI of 42.8 ± 7.5 kg/m² (range 31–70). Most patients were Italian (n = 150). One patient was illiterate, 8 had primary school diploma, 61 had secondary school diploma, 76 had high school degree, and 17 had graduated from university. Out of 163 participants, 1 was student (0.61%), 24 were housewife (14.72%), 7 retired (4.29%), 24 unemployed (14.72%), and 107 office workers (65.66%).

As regards to comorbidities, 82 patients had gastric pyrosis (50.31%), 75 had hypertension (46.01%), 53 had osteoarthritis (32.52%), 47 had hypercholesterolemia (29.01%), 43 had obstructive sleep apnea (26.38%), 36 had diabetes (22.09%), 27 had urinary incontinence (16.56%), and 24 had venous ulcers (14.72%). None of the patients had all comorbidities; 28 had no comorbidities at all. One hundred one had two or more, and 67 had three or more.

In the physical domain of the SF-36 questionnaire, the patients had a median score of 38.5, interquartile range (IQR) = [31.4–47.7], indicating poor outcomes in the physical dimensions of quality of life. The mental components had a median score of 41.9, IQR = [32.7–50.9], still corresponding to low levels of quality of life.

The median score in the Rosenberg self-esteem questionnaire (psychological well-being) was 18, IQR = [14–23], indicating normal levels of self-esteem; however, 42 patients had Rosenberg scores below 15, indicating low self-esteem.

According to the results of the Beck Depression Inventory, 80 patients had no signs of depression; 31, 21, and 31 participants had low, moderate, and high levels of depression, respectively.

The ORWELL questionnaire had a median score of 149, IQR = [115–191] out of a possible range between 18 and 288. In this questionnaire, the higher scores represent a lower quality of life. Therefore, the median score obtained by our patients indicates poor quality of life in the domains investigated by the questionnaire.

The overall median scores in each domain of the Laval questionnaire are reported in Table 1.

Table 1.

Median Scores in the Laval Domains

Domain	Median	IQR
Activity	4	3–5.5
Symptoms	4	3–5
Hygiene	4	3–5
Emotions	4	3–5
Social interactions	5	4–6
Sexual life	4	3–5
Total QoL	26	19–31

IQR, interquartile range.

Characteristics of the Laval Questionnaire

The Laval questionnaire showed excellent internal consistency, with high Cronbach's alpha coefficients (0.93 and 0.94, respectively, during the assessment at baseline and after 2 weeks).

Because this study also aimed to investigate correlation between the Laval questionnaire and the other tools, we assessed the internal consistency of the SF-36, Rosenberg, Beck Depression Inventory, and ORWELL questionnaires as well, to verify if such tools were suitable for being used in our sample. All alpha coefficients were satisfactory (0.86, 0.87, 0.94, and 0.92 respectively).

Kaiser-Meyer-Olkin's measure of sampling adequacy was excellent (0.95) and the result of Bartlett's sphericity test was significant (p < 0.0001). Therefore, we proceeded with factor analysis, which pointed out a single eigenvalue complying with Kaiser's criterion of being >1 (actual value: 4.29). The factor loadings of such eigenvalue, calculated by taking into account the six domains of the questionnaire, as identified by the original authors, were all retained, since they all satisfied Steven's criterion [5.152/√(163–2)]. This analysis pointed out that the factor loadings corresponding to the six domains were of great importance in the overall construct of the scale, thus confirming the strict logical process behind the assessment conducted with the Italian version of the Laval questionnaire in this kind of patients, as well as the adherence of the Italian version to the construct conceived by the original authors.

Table 2 reports the factor loadings.

Table 2.

Factor Loadings in the Italian Version of the Laval Questionnaire

Variable	Loading
Activity	0.88
Symptoms	0.85
Hygiene	0.86
Emotions	0.88
Social interactions	0.83
Sexual life	0.76

The Italian version of the Laval questionnaire showed strong and significant correlation with the ORWELL scores (Spearman's ρ = −0.78, confidence interval [95% CI]: 0.836 to −0.716, p < 0.001). Correlation was negative because high Laval scores indicate good quality of life, and vice versa for the ORWELL questionnaire.

Correlations between the psychological domains of the Italian Laval tool and the Rosenberg total score were satisfactory (ρ = 0.72, 95% CI: 0.635–0.785 and ρ = 0.69, 95% CI: 0.59–0.76, respectively, p < 0.001 in both calculations).

Correlations between all domains of the Italian Laval questionnaire and the total Beck Depression Inventory tool were satisfactory and highly significant (p < 0.001 for all calculations).

Correlation with the SF-36 scores was satisfactory, in both physical and mental domains. All correlations were highly significant (p < 0.001). The mental domain of the SF-36 was correlated with the Laval domains “emotions” (ρ = 0.66, 95% CI: 0.56–0.74), “sexual life” (ρ = 0.51, 95% CI: 0.39–0.62), and “social interactions” (ρ = 0.57, 95% CI: 0.45–0.66). The physical domain was correlated with “activity” (ρ = 0.62, 95% CI: 0.52–0.71), “hygiene” (ρ = 0.54, 95% CI: 0.42–0.64), and “symptoms” (ρ = 0.63, 95% CI: 0.53–0.72). The correlation coefficients, although not very high, are statistically significant.

Table 3 summarizes the results.

Table 3.

Confidence Interval for Spearman's Rank Correlation Between the Laval Questionnaire and Related Instruments

Laval questionnaire domains
	Laval total scores (95% CI), p	Symptoms (95% CI), p	Activity/mobility (95% CI), p	Personal hygiene/clothing (95% CI), p	Emotions (95% CI), p	Social interactions (95% CI), p	Sexual life (95% CI), p
ORWELL total score	−0.78 (−0.84 to 0.72), p < 0.001
Rosemberg Self-Esteem Scale—Total score	0.67 (0.58 to 0.75), p < 0.001				0.69 (0.64–0.78), p < 0.001	0.72 (0.59–0.76), p < 0.001
Beck Depression Inventory tool—Total score	−0.74 (−0.81 to −0.67), p < 0.001	−0.63 (−0.72 to −0.53), p < 0.001	0.61 (−0.69 to −0.50), p < 0.001	−0.60 (−0.69 to 0.49), p < 0.001	−0.75 (−0.81 to 0.67), p < 0.001	−0.69 (−0.76 to −0.59), p < 0.001	−0.57 (−0.67 to −0.46), p < 0.001
SF-36 Mental Component Score (MCS)	0.59 (0.48–0.68), p < 0.001				0.66 (0.56–0.74), p < 0.001	0.56 (0.45–0.66), p < 0.001	0.51 (0.39–0.62), p < 0.001
SF-36 Physical Component Score (PCS)	0.51 (0.39–0.62), p < 0.001	0.63 (0.53–0.72), p < 0.001	0.62 (0.52–0.71), p < 0.001	0.53 (0.42–0.64), p < 0.001

CI, confidence interval.

Discussion

Obesity affects about 10% of the adult population²² and is often complicated by the presence of depression and compromised quality of life.^6–8

To evaluate changes in quality of life, generic scales such as the Short Form-36 are often used in different study^9,14,23: they can be used in a variety of different medical conditions, but are not suitable to assess the potential issues regarding specific health problems such as obesity.²⁴ Specific tools for a given disease are more sensitive to changes occurring during surgical treatments of obesity, because they use specific items to inquire specific aspects of quality of life.^23,25 The only specific questionnaire developed in Italy is the Obesity-Related Well-Being Scale (ORWELL 97), including 18 items that explore only the physical dimension of quality of life with symptoms related to BMI, without focusing on the psychosocial dimensions.²³

The overall purpose of this study was to assess the validity and reliability of the Italian version of the Laval Questionnaire for the assessment of Health-related Quality of Life (HRQoL) in patients with obesity who undergo bariatric surgery.

The reliability and internal consistency of the new questionnaire Laval in the Italian version were excellent, both at time 0 and time 1, with Cronbach's alpha values very similar to those obtained during validation of the original Canadian instrument.

We used factor analysis to identify complex interrelationships among items and group items that are part of similar concept in different tools: the results showed a medium–high relationship between each construct of Laval and the same constructs identified by the items of the other questionnaires, except for the component “sexual life,” for which the relationship were slightly weaker (0.61 for Canadian version, which compared “sexual life” domain of Laval questionnaire with “sexual life” domain of IWQOL-Lite; 0.51 for Italian version, which compared “sexual life” domain of Laval questionnaire with “Mental Health” domain of SF-36).

The correlation of the domain “emotions” of Laval Questionnaire with the Beck Depression Inventory is moderate and almost comparable to that obtained from the Canadian version.

As regards the SF-36, physical and mental domains were related, respectively, to different domains of Laval: the physical domain was related to “activities,” “hygiene,” and “symptoms”; the mental domain was related to “emotion,” “sexual life,” and “social interaction.” The areas of Laval are properly distributed and related to the different domains of the SF-36. Although correlation was moderate, the results were satisfactory: it should be taken into account that the SF-36 is a generic measure of quality of life, whereas the Laval tool is more specific. This might partially justify the values of the correlation coefficient. Generic tools in fact are less likely to detect change in quality of life than disease-specific questionnaires, which focus on specific areas of quality of life. As a consequence, generic questionnaires are usually less sensitive to change than disease-specific instruments,⁸ a situation that was also observed in a Canadian validation study. In contrast to the findings in the validation study of the original instrument for which the correlation coefficient was low, the psychological domain of the Italian version presented a good correlation with the results of the Rosenberg Self-Esteem Scale, thus highlighting that the Italian version has a good ability to assess the mental dimension.

Finally, we analyzed the correlation with the more specific questionnaire used in the Italian reality, the ORWELL-97: it has proved very satisfactory. The Laval appears therefore more similar and more correlated to the specific measures for people suffering from morbid obesity than generic measures, such as the SF-36.

Table 4 shows the Correlation coefficients between the Canadian version and the various tools, also used for validation of the Italian version.

Table 4.

Correlation Coefficients Between the Canadian Version and the Tools, Also Used for Validation of the Italian Version

Laval questionnaire domains
	Symptoms	Activity/mobility	Personal hygiene/clothing	Emotions	Social interactions
SF-36
Physical functioning		0.67^a	0.58^a
Role–physical		0.75^a	0.59^a
Bodily pain	0.70^a
General Health perception	0.57^a
Energy/vitality	0.62^a			0.61^a
Social functioning					0.58^a
Role–emotions				0.53^a
Mental health				0.71^a
Rosemberg Self-Esteem Scale—Total score				0.24^a
Beck Depression Inventory tool—Total score				−0.77^a

For all coefficients p ≤ 0.01.

As regards depression, assessed through the Beck Depression Inventory, our results show that >50% of subjects in the sample presented symptoms of depression to a certain level (low, moderate, or high). The same occurred with regard to self-esteem, with 42 of 80 subjects with unsatisfactory self-esteem, evaluated with the Rosemberg Self-Esteem Scale. These results agree with the findings from the literature: people suffering from morbid obesity, especially if looking for a surgical therapy, have an impairment of the psychological component of HRQoL.^11,26 They refer, in fact, very often low levels of self-esteem, high levels of dissatisfaction with their bodies, and depression related to the weight¹¹; these issues are going to affect negatively the functionality of psychological subjects, also causing role limitations due to emotional problems. The impairment of psychoemotional dimension of the HRQoL is also linked to the perception of discrimination or derision that individuals with obesity often live and perceive.⁷ The stigma and prejudice that are often experienced and suffered by the subject with obesity appear to be associated with a lower quality of life and more symptoms of depression.^20,27,28

Conclusion

The results of this study support the validity and reliability of the Italian version of the Laval Questionnaire for the assessment of HRQoL in patients with obesity who undergo bariatric surgery. This tool has a high relevance of the questions with respect to the construct investigated and the HRQoL, and has good internal consistency and high accuracy.

The assessment of QoL in patients with morbid obesity who await the surgical procedure is important because the improvement of HRQoL is one of the primary purposes of bariatric surgery: an improvement in HRQoL reported by the patient represents a rate of success of surgery. In addition, the HRQoL as subjectively reported by patients before the intervention can provide information about the expected outcome of treatment in terms of weight loss: it is shown that subjects who preoperatively were more dissatisfied with their HRQoL are the ones who get most benefit from surgery.¹⁴

Although different tools for evaluation of QoL exist in Italian language, only a few have developed specifically for obese individuals in the obese patient: generic tools are less useful in assessing disorders and discomforts closely related to obesity. Nowadays in Italy, the existing specific instruments only evaluate physical symptoms related to obesity, without investigating the impact of the disease on psychosocial aspects of HRQoL. The Laval questionnaire, in its Italian version, has proved to be a valid tool for the assessment of all aspects of HRQoL. Furthermore, it is specific for use in the contexts of bariatric surgery: the Laval Questionnaire appears to be a very specific instrument for patients with morbid obesity who intend to undergo interventions of bariatric surgery (gastric bypass and gastric banding), which can be extremely useful in clinical contest to monitor the effectiveness of treatments and changes in HRQoL induced by surgery. A more extensive use of Laval Questionnaire would be useful, even in reality of central and southern Italy, to confirm the results obtained in this study.

Authors' Contributions

Dr. R.A. and Prof. A.D conceived the study, Dr. S.T. and Dr. R.A. performed the statistical analysis, and Dr. S.R. and Dr. E.R. supervised the clinical content of the study and helped in data collection.

Footnotes

Disclosure Statement

No competing financial interests exist.

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