“Patients with amyotrophic lateral sclerosis (ALS) are usually nice persons”—How physicians experienced in ALS see the personality characteristics of their patients

Abstract Introduction Physicians experienced in the treatment of patients with amyotrophic lateral sclerosis (ALS) occasionally describe these patients as “nice” persons. Methods ALS experienced physicians (n = 36) were asked to assess the personality characteristics of ALS patients using a multidimensional personality questionnaire based on the five‐factor model of personality. Control groups consisted of physicians experienced in Myasthenia gravis (MG) (n = 21) and lung cancer (LC) (n = 36). Results In the dimension Agreeableness ALS patients were rated significantly higher than the other groups (p < .001). This was mainly due to the high scores for converse adjective pairs “stubborn—compliant” and “selfish—helpful”. Discussion The dimension Agreeableness is very similar to “niceness”. Results support the anecdotal description of ALS patients as “nice” persons. Personality characteristics of ALS patients differentiate them from other patient groups. It remains open whether the “nice” personality structure is linked to the susceptibility to the disease.

(NEO-PI-R) (Grossman, Levin, & Bradely, 2006). In this study ALS patients showed significantly higher values for the personality dimension called "Openness" compared to non-ALS patients.
In the present study, a multidimensional personality questionnaire was used to analyze systematically how experienced physicians assessed the personality structure of ALS patients. In contrast to previous studies on patients themselves or their relatives (Grossman et al., 2006;Peters et al., 1978), we asked experienced physicians. The presence of an ALS-specific personality could result in development of individual psychological treatment methods for dealing with these patients.

| PATIENTS AND METHODS
The personality characteristics of ALS patients were assessed by neurologists from neuromuscular centers in Germany using a shortened version of the "NEO Five-Factor Inventory" (NEO-FFI) (Borkenau & Ostendorf, 2003). This version consists of a total of 30 converse pairs of adjectives that represent the most basic dimensions of personality based on the established five-factor model: Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness. Consequently, there were six pairs of adjectives for each dimension. Clinicians were asked to rate for each pair using a five-point score which best describes the "average" ALS patient (0 = strongly agree to the negative pole, 1 = agree to the negative pole, 2 = neutral, 3 = agree to the positive pole of the dimension, and 4 = strongly agree to the positive pole of the dimension).
Thus, for every dimension a maximum score of 24 could be reached. This group consisted of specialists for medical oncology, pulmonology, and radiotherapy. All expert groups received the same personality questionnaire (shortened NEO-FFI) by mail between October 2014 and August 2015. Additionally, a reminder letter was sent by mail after 4 weeks. In order to ensure an appropriate expertise with the particular patient group, the level of expertise was assessed as follows: (1) number of treated ALS patients per year (1 = less than 6 patients, 2 = 6-12 patients, 3 = more than 12 patients) and by (2) duration of practice (1 = less than 2 years, 2 = between 2 and 4 years, 3 = more than 4 years). Consequently, total score of experience could range between 2 and 6. The same scoring system was applied to the LC and MG experts.

| Statistical analysis
A univariate analysis of variances (ANOVA) was calculated to investigate differences in physicians ratings of the five personality dimensions for ALS, MG, and LC patients. Normal distribution of data was tested using the Kolmogorov-Smirnov test. Possible deviations from the assumption of variance homogeneity were tested using the Levene test. Because of the multiple testing, a post hoc analysis with the conservative Scheffe's test was conducted with the relevant 95% confidence intervals (CI). This test performs a complex group comparison based on linear combinations and can also be used for groups of different sizes. p-Values <.05 were considered significant. All tests were two tailed. Data were processed using the Statistical Package for Social Sciences program version 20. Missing data were not included in the statistical analysis.

| Ethical standards
The manuscript does not contain clinical studies or patient data.

| RESULTS
A total of 60 questionnaires were sent by mail to each expert group,

| DISCUSSION
The obtained results support the occasional statements that ALS patients are usually "nice" (Borasio & Miller, 2001;Wilbourn & Mitsumoto, 1998) persons. Niceness is not a dimension of the five-factor model of personality, but it is very close to the dimension Agreeableness.
Persons with high scores on the dimension Agreeableness can be described as warm, nice, and kindhearted persons who meet other persons with goodness and helpfulness (Ostendorf & Angleitner, 2004).
Within the five personality dimensions, only Agreeableness showed an ALS-specific significant difference. None of the other personality dimensions achieved statistical significance between the ALS and the other expert groups.
In a caregiver-based (mainly relatives) study which evaluated the premorbid personality, ALS patients had a lower score on the dimension Openness compared to patients with LC (Grossman et al., 2006).
A low score on that dimension describes a more factually oriented person with traditional and conventional values who tend to comply with the physicians instructions (Borkenau & Ostendorf, 2003). This increased willingness to follow the medical advice prompt clinicians to perceive the ALS patients as nicer and more cooperative than other patient groups. This assessment of caregivers is consistent with the assessment made by clinicians in this study.
However, it cannot be excluded that a feeling of compassion for the patients with the dramatic course of the disease influences the positive judgment of physicians and caregivers. In both studies, there was not such a positive assessment of the patients with LC that also have a poor prognosis. The study does not necessarily imply that similar results would be found in a direct survey of the patients themselves.
A possible limitation might be the use of a shortened version of the questionnaire NEO-FFI. However, the applied questionnaire followed very close to the well-validated NEO-FFI and the adjectives to assess the five dimensions are defined in the official manual.
In conclusion, this study indicates that there seems to be a specific personality structure common in patients with ALS. It remains open if this personality is linked to the susceptibility of the disease.

ACKNOWLEDGMENTS
We would like to thank all the physicians for participating in this study.
Those who have disclosed their names are as follows: T Behlendorf