General life satisfaction refers to a “global assessment of all aspects of a person’s life” (Diener, 1984, p. 544). It represents the cognitive-evaluative component of subjective well-being, in contrast to the affective component that comprises the frequency of positive and negative emotions in life (Andrews & Withey, 1976; Diener, 1984; Lucas et al., 1996). In his seminal paper on subjective well-being (which comprises life satisfaction, positive and negative affect), Diener (1984) underlined the construct’s importance by gathering information on diverse correlates such as personality, health, and lots of socio-structural characteristics such as income, age, gender, employment status, and education. Especially in the past two decades, there has been a surge in research on life satisfaction, its life-span development, its factors that influence it, and its relation to other variables such as life events (for an overview, see Luhmann, 2017). Consistent positive associations have been found, for instance, between life satisfaction and the Big Five personality traits, the strongest with Emotional Stability (e.g., Grevenstein et al., 2018; Heidemeier & Göritz, 2016), interpersonal trust (e.g., Jovanović, 2016; Wang et al., 2019), optimism (e.g., Hajek & König, 2019; Ozmen et al., 2018), general self-efficacy (e.g., Judge et al., 2005; Moksnes et al., 2019), self-esteem (e.g., Gomez-Baya et al., 2018; Pérez-Fuentes et al., 2019), health (e.g., Bomhoff & Siah, 2019; Hajek & König, 2019), and income (e.g., Cheung & Lucas, 2015; Pinquart & Sörensen, 2000).

Considering its association with various constructs and variables, life satisfaction is frequently surveyed in (inter-)national surveys such as the German Socio-Economic Panel (SOEP), the Household, Income and Labour Dynamics in Australia (HILDA), and the international World Values Survey (WVS). A variety of measurements have been developed to track general life satisfaction. Although multi-item scales to measure life satisfaction exist (see for example the five-item Satisfaction With Life Scale [SWLS]; Diener et al., 1985), life satisfaction is most often assessed with a single-item Likert-type scale. In single-item measures, respondents are usually asked to rate their satisfaction with their overall life on a scale ranging from "very dissatisfied" to "very satisfied". However, the operationalization in terms of item wordings and the description and number of the response categories differ between the surveys. Psychometric properties of the different operationalizations are unknown. Therefore, Beierlein, Kovaleva, László, et al. (2015) optimized and psychometrically evaluated the single-item operationalization used in SOEP (Richter et al., 2013) to arrive at a psychometrically sound German-language source version of general life satisfaction: the General Life Satisfaction Short Scale (L-1).

Item generation and selection

To develop the German-language source version of L-1, Beierlein, Kovaleva, László, et al. (2015) drew on the existing—not validated—single-item measure of life satisfaction (Wagner, 2007) that had been used in the longitudinal German survey SOEP. This item and its rating scale were revised to align them with best practices of scale construction (e.g., a unipolar instead of a bipolar rating scale was used). Two different rating scales were tested using item and distribution analyses (for more detailed information, see Beierlein, Kovaleva, László, et al., 2015). The German-language L-1 was thoroughly validated based on a large and diverse random sample representative of the adult population in Germany in terms of age, gender, and educational attainment.

Because researchers may be interested in comparing the level of general life satisfaction between different societies, there is a need for a cross-culturally valid measure. To enhance the usability of L-1, and to enable social surveys to use L-1 in an English-language context, the scale was adapted to the English language (by Beierlein, Kovaleva, László, et al., 2015) and validated in a sample from the UK (in the present study). First, the one item of L-1 and its rating scale were adapted to English by translating the item and the rating scale following the TRAPD approach (Translation, Review, Adjudication, Pretesting, and Documentation; Harkness, 2003), whereby two professional translators (English native speakers) translated the item and the rating scale independently of each other into British English and American English, respectively. Second, an adjudication meeting was held where psychological experts, the two translators, and an expert in questionnaire translation reviewed the translation proposals and developed the final translation.

The source instrument by Beierlein, Kovaleva, László, et al. (2015) was developed in and validated for the German language. The aim of the present study was to validate the English-language adaptation of L-1 and to directly compare its psychometric properties with those of the German-language source version.

Samples

To investigate the psychometric properties of the English-language adaptation of L-1, and their comparability with those of the German-language source instrument, we assessed both versions in a web-based survey (using computer-assisted self-administered interviewing [CASI]) conducted in the UK and Germany (DE) by the online access panel provider respondi AG. Fielding took place in January 2018. For both the UK and Germany, quota samples were drawn that represented the heterogeneity of the adult population with regard to age, gender, and educational attainment. Only native speakers of the respective languages were recruited. Our research goal (investigation of the quality of several questionnaires) was explained to the participants. Respondents were financially rewarded for their participation. In both nations, a subsample was reassessed after approximately 3 to 4 weeks (median time intervals: 28 days in the UK and 20 days in Germany).

Only respondents who completed the full questionnaire—that is, who did not abort the survey prematurely—were included in our analyses. To handle missing values on single items, we used full information maximum likelihood estimation (FIML) in our analyses. The gross sample sizes were N_UK = 508 and N_DE = 513. In the next step, invalid cases were excluded based on (a) ipsatized variance—that is, the within-person variance across items (Kemper & Menold, 2014)—if the person fell within the lower 5% of the sample distribution of ipsatized variance; (b) the Mahalanobis distance of a person’s response vector from the average sample response vector (Meade & Craig, 2012) if the person fell within the upper 2.5% of the sample distribution of the Mahalanobis distance; and (c) response time, namely, if the person took, on average, less than 1 s to respond to an item. Our intention in choosing relatively liberal cut-off values was to avoid accidentally excluding valid cases. All exclusion criteria were applied simultaneously, that is, any respondent who violated one or more of the three criteria was excluded from the analyses and that only those who met all three criteria were included. This approach resulted in total exclusion of 40 cases (7.9%) in the UK subsample and 39 cases (7.6%) in the German subsample, yielding net sample sizes of N_UK = 468 (retest: N_UK = 111) and N_DE = 474 (retest: N_DE = 117). Table 2 depicts in detail the sample characteristics and their distribution.

Table 2

Sample Characteristic Features

Note. The equivalent German educational levels were as follows (from low to high): ohne Bildungsabschluss/Hauptschule [no educational qualification; lower secondary leaving certificate]; mittlerer Schulabschluss [intermediate school leaving certificate]; (Fach-)Hochschulreife [higher education entrance qualification].

Material

Online surveys were conducted in German for the German sample and in English for the UK sample. They comprised the respective language version of L-1. In addition, the following short scale measures were also administered as part of the survey to explore the nomological network of L-1 against (a) the Big Five personality traits, (b) risk proneness, (c) impulsive behavior, (d) optimism–pessimism, (e) general self-efficacy, (f) self-esteem, (g) locus of control, (h) interpersonal trust, (i) injustice sensibility, (j) socially desirable responding, (k) political efficacy, and (l) health, respectively:

(a)     the extra-short form of the Big Five Inventory–2 (BFI-2-XS; English version: Soto & John, 2017; German version: Rammstedt et al., 2020)

(b)     the Risk Proneness Short Scale (R-1; Nießen, Groskurth, et al., 2020; German version: Kurzskala zur Erfassung der Risikobereitschaft; Beierlein, Kovaleva, Kemper, et al., 2015)

(c)     the Impulsive Behavior Short Scale–8 (I-8; Groskurth et al., 2022 ; German version: Skala Impulsives Verhalten-8; Kovaleva et al., 2014a)

(d)     the Optimism–Pessimism Short Scale–2 (SOP2; Nießen, Groskurth, et al., 2022 ; German version: Skala Optimismus-Pessimismus-2; Kemper, Beierlein, Kovaleva, et al., 2014)

(e)     the General Self-Efficacy Short Scale–3 (GSE-3; Doll et al., 2021; German version: Allgemeine Selbstwirksamkeit Kurzskala; ASKU; Beierlein, Kovaleva, et al., 2014)

(f)     the Rosenberg Self-Esteem Scale (RSES; English version: Rosenberg, 2014; German version: von Collani & Herzberg, 2003)

(g)     the Internal–External Locus of Control Short Scale–4 (IE-4; Nießen, Schmidt, et al., 2022 ; German version: Internale-Externale-Kontrollüberzeugung–4; Kovaleva et al., 2014b)

(h)     the Interpersonal Trust Short Scale (KUSIV3; Nießen, Beierlein, et al., 2020; German version: Kurzskala Interpersonelles Vertrauen; Beierlein et al., 2014a)

(i)     the Justice Sensitivity Short Scales–8 (JSS-8; Groskurth et al., 2023; German version: Ungerechtigkeitssensibiliät-Skalen-8; USS-8; Beierlein, Baumert, et al., 2014)

(j)     the Social Desirability–Gamma Short Scale (KSE-G; Nießen et al., 2019; German version: Soziale Erwünschtheit–Gamma; Kemper, Beierlein, Bensch, et al., 2014)

(k)     the Political Efficacy Short Scale (PESS; Groskurth et al., 2021; German version: Political Efficacy Kurzskala; PEKS; Beierlein et al., 2014b)

(l)     the single-item question used in the European Social Survey (ESS, 2016) to measure self-reported general health

In addition, a set of sociodemographic variables was measured: gender, age, highest level of education, income, and employment status (1 = employed, 2 = self-employed, 3 = out of work and looking for work, 4 = out of work but not currently looking for work, 5 = doing housework, 6 = pupil/student, 7 = apprentice/internship, 8 = retired, 9 = none of what is mentioned above).

Item analyses

Because L-1 is a single-item measure, item analyses are not applicable. The analysis code for all the other analyses was run with R and can be found in the Appendix.

Item parameters

Table 3 shows the mean, standard deviation, skewness, and kurtosis for the one L-1 item, separately for the English and German samples. The kurtosis showed to be different in both nations and the distribution in Germany showed to be slightly more left-skewed.

Table 3

Descriptive Statistics for the L-1 Item

Note. UK = United Kingdom (N = 468); DE = Germany (N = 474).

To validate the English-language adaptation of L-1 and to investigate its comparability with the German-language source version, we analyzed psychometric criteria—objectivity, reliability, and validity—in both language versions.

Objectivity

A scale can be regarded as objective when it works (a) independently of the administrator (objectivity of application); (b) independently of the evaluator of the test (objectivity of evaluation); and (c) when unambiguous and user-independent rules are provided (objectivity of interpretation). The standardized questionnaire format and written instructions, the fixed scoring rules and labeled categories, and the reference ranges ensured the objectivity of the application, evaluation, and interpretation of L-1.

Reliability

As estimate for the reliability of L-1, we computed the test–retest stability over a fifteen-to-thirty-one-day period. Our reasoning was that 2 to 4 weeks are a time span that is long enough to allow for meaningful test–retest stability estimates while being short enough to preclude the occurrence of pronounced and systematic change in the true scores of life satisfaction. The resulting reliability is best understood as lower-bound estimate, as the test–retest stability is sensitive not only to measurement error but also to state fluctuations in life satisfaction.

As Table 4 shows, the test–retest reliability estimate for L-1 was .82 (UK) and .71 (DE), which can be deemed sufficient for most research purposes (Aiken & Groth-Marnat, 2006; Kemper et al., 2019). In detail, L-1 proved to be more reliable in the UK than in Germany.

Table 4

Reliability Estimates for L-1

Note. UK = United Kingdom (N = 468; retest: N = 111); DE = Germany (N = 474; retest: N = 117); CI = confidence interval. The time interval between test and retest ranged between 15 and 31 days (Mdn_UK = 28 days; Mdn_DE = 20 days).

Validity

Besides content-related evidence, which was ensured by Beierlein, Kovaleva, László, et al. (2015) during the original scale development process, we investigated validation evidence based on the relationship between scores on the scale and on other variables.

Evidence based on the relationship between scores on L-1 and on other variables was computed based on manifest correlations. Therefore, the reported values probably represent the lower bound of the true associations. The correlation coefficients are depicted in Table 5; their interpretation is based on Cohen (1992): small effect (r ≥ .10), medium effect (r ≥ .30), and strong effect (r ≥ .50). Due to alpha accumulation through multiple testing, only coefficients with a significance level above p < .001 are interpreted (Table 5 displays unadjusted p values). Before computing the correlations, we recoded the health variable (for both language versions), the “minimizing negative qualities” subdimension of socially desirable responding (for both language versions), and the self-esteem scale (UK only) so that high values represented high self-esteem, high socially desirable responding, and high health values, respectively. In addition, we recoded the employment status variable and tested four different categories against the reference category employed: (a) self-employed vs. employed; (b) unemployed (out of work and looking for work/out of work but not currently looking for work) vs. employed/self-employed; (c) retired/doing housework vs. employed/self-employed; and (d) pupil/student/apprentice/internship vs. employed/self-employed.

In order to investigate this type of evidence, we correlated L-1 with the following constructs: (a) the Big Five dimensions Extraversion, Agreeableness, Conscientiousness, Emotional Stability, and Openness assessed with the BFI-2-XS (Rammstedt et al., 2020; Soto & John, 2017); (b) risk proneness assessed with R-1 (Beierlein, Kovaleva, Kemper, et al., 2015; Nießen, Groskurth, et al., 2020); (c) four aspects of impulsive behavior assessed with I-8 (Groskurth et al., 2022 ; Kovaleva et al., 2014a); (d) optimism and pessimism assessed with SOP2 (Kemper, Beierlein, Kovaleva, et al., 2014; Nießen, Groskurth, et al., 2022); (e) general self-efficacy assessed with GSE-3 (Doll et al., 2021)/ASKU (Beierlein, Kovaleva, et al., 2014); (f) self-esteem assessed with RSES (Rosenberg, 2014; von Collani & Herzberg, 2003); (g) internal locus of control (an individual’s belief that an event is dependent on his own behavior or stable personality characteristics; Rotter, 1966) and external locus of control (an individual’s belief that an event is the result of luck, chance, fate or under the control of powerful others; Rotter, 1966) assessed with IE-4 (Kovaleva et al., 2014b; Nießen, Schmidt et al., 2022); (h) interpersonal trust assessed with KUSIV3 (Beierlein et al., 2014a; Nießen, Beierlein, et al., 2020); (i) four subdimensions of injustice sensibility assessed with JSS-8 (Groskurth et al., 2023)/USS-8 (Beierlein, Baumert, et al., 2014); (j) two aspects of socially desirable responding (exaggerating positive qualities and minimizing negative qualities) assessed with KSE-G (Kemper, Beierlein, Bensch, et al., 2014; Nießen et al., 2019); (k) internal political efficacy (individual’s belief of having political means of influence; Balch, 1974) and external political efficacy (individual’s belief that the government responds to influence attempts; Balch, 1974) assessed with PESS (Groskurth et al., 2021)/PEKS (Beierlein et al., 2014b); and (l) self-reported general health assessed with the single-item question used in the ESS (2016).

Correlations with convergent and discriminant constructs

With regard to personality in terms of the Big Five dimensions, previous research suggests correlations between life satisfaction and all Big Five dimensions, the strongest with Emotional Stability and the weakest with Openness (e.g., Brajša-Žganec et al., 2011; DeNeve & Cooper, 1998; Grevenstein et al., 2018; Grevenstein & Bluemke, 2015; Heidemeier & Göritz, 2016). In addition, zero correlations with Openness, Agreeableness, or Conscientiousness have been consistently reported (e.g., Anglim et al., 2020; Anglim & Grant, 2016; Nishimura & Suzuki, 2016). In the present analyses, we could replicate these differing findings, because we also found these different patterns across the two nations. Consistent across the two nations, there was a large positive association with Emotional Stability, a small-to medium positive association with Extraversion, and no association with Conscientiousness. For the UK sample, there were small positive correlation between life satisfaction and Agreeableness and no correlation with Openness, whereas there was a small positive relation to Openness and no relation to Agreeableness in the German sample.

With respect to optimism–pessimism, general self-efficacy, self-esteem, and health, we could replicate the findings of the German-language source version. Consistent with a variety of other previous findings, including those of Beierlein, Kovaleva, László, et al. (2015), we found—for both the UK and Germany—small-to-large positive relations with optimism (e.g., Hajek & König, 2019; Kemper, Beierlein, Kovaleva, et al., 2014; Ozmen et al., 2018; Rezaei & Khosroshahi, 2018), general self-efficacy (e.g., Beierlein, Kovaleva, et al., 2014; Hajek & König, 2019; Judge et al., 2005; Moksnes et al., 2019), self-esteem (e.g., Gomez-Baya et al., 2018; Hajek & König, 2019; Judge et al., 2005; Pérez-Fuentes et al., 2019), and health (e.g., Bomhoff & Siah, 2019; Habibov & Afandi, 2016; Hajek & König, 2019; Heidl et al., 2012; Kööts-Ausmees & Realo, 2015; Watten et al., 1997). Individuals high in optimism, general self-efficacy, self-esteem, and who reported a high general health status had a high propensity for also reporting a high life satisfaction.

Concerning socially desirable responding, we could not support the findings from Beierlein, Kovaleva, László, et al. (2015), who reported a small negative relation to “exaggerating positive qualities” and a small positive relation to “minimizing negative qualities”. Instead, we found no correlations between life satisfaction and socially desirable responding in the German sample, whereas in the UK sample there was a small positive effect for the “exaggerating positive qualities” subscale (see also Caputo, 2017; Jang & Kim, 2009; Leising et al., 2016), which depicts the self-deceptive enhancement component of communion-induced socially desirable responding (Nießen et al., 2019).

In line with previous research (e.g., Beierlein, Kovaleva, Kemper, et al., 2015; Dohmen et al., 2011; Muffels & Headey, 2013), there was a small positive association between life satisfaction and risk proneness (UK only, with a tendency to the same effect for the German sample). Individuals high in risk proneness had a high propensity for a high life satisfaction.

Regarding impulsive behavior, in the UK sample, there was a small positive effect for the subdimensions “premeditation” and “perseverance” (see also Kovaleva et al., 2014a; note that Kovaleva and colleagues correlated the four subdimensions of impulsive behavior with job satisfaction; Wiese et al., 2018; but see Machado et al., 2019, who found a negative association between life satisfaction and impulsivity), whereas in the German sample, there was only a small positive correlation with the subdimension “perseverance”. Individuals who had no “difficulty in thinking and reflecting on the consequences of an act before engaging in that act” and those who had no ”difficulty completing projects and working under conditions that require resistance to distracting stimuli” (Whiteside et al., 2005; p. 561) tended to have a high life satisfaction. In contrast, there were no associations with the other subdimensions “urgency” and “sensation seeking” (see also Oishi et al., 2001).

In addition, we found a small-to-medium positive relation between life satisfaction and internal locus of control (see also Judge et al., 2005; Osborne et al., 2016; note that these authors did not differentiate between internal and external locus of control) and a medium negative relation between life satisfaction and external locus of control (DE only, with a tendency to the same but small effect for the UK sample; see also Au, 2015; Karaman et al., 2017; note that these authors did not differentiate between internal and external locus of control). Both findings are consistent with evidence from Kovaleva et al. (2014b): High life satisfaction was associated with an individual’s belief that an event is dependent on his own behavior and not under the control of powerful others.

Consistent across the two nations, there was a medium positive effect for interpersonal trust (see also Barefoot et al., 1998; Beierlein et al., 2014a; Jovanović, 2016; Wang et al., 2019), a small negative effect for the “victim sensitivity” subscale of injustice sensibility (see also Beierlein, Baumert, et al., 2014; Sturgeon et al., 2017), and small positive effects for both internal and external political efficacy (see also Whiteley et al., 2010; note that Whiteley and colleagus did not differentiate between internal and external political efficacy). Individuals scoring high in interpersonal trust and political efficacy and those who did not perceive themselves in a victim’s perspective had a high tendency to report a high life satisfaction.

In sum, some clear similarities but also some major differences among both nations should be highlighted. First, in both nations, there was consistently a positive relation to the Big Five dimensions Emotional Stability and Extraversion, to the subscale “perseverance” of impulsive behavior, to optimism, general self-efficacy, self-esteem, internal locus of control, interpersonal trust, internal and external political efficacy, and the health status and a negative relation to the subdimension “victim sensitivity” of injustice sensibility. Second, the associations with the Big Five dimensions Agreeableness and Openness, with risk proneness, and with the subscale “exaggerating positive qualities” of socially desirable responding were slightly different: For three of these constructs (but Openness), in the UK, there was a positive association with life satisfaction, whereas in Germany, we only found tendencies in the same direction. In the case of Openness, it was vice versa with a positive association in Germany and no association in the UK. Third, the only correlation that proved to be completely different between both nations was the subscale “premeditation” of impulsive behavior: There was a positive correlation with life satisfaction in the UK but a zero correlation in Germany. Even though we found—among others—partially slightly different correlations in both nations, overall, the pattern of correlations confirms evidence based on scale–construct relationships of L-1.

Correlations with sociodemographic characteristics

We calculated correlations between L-1 and relevant sociodemographic characteristics, namely employment status, income, educational level, age, and gender. In the present analyses, consistent across the two nations, we found medium correlations with income. Individuals with a high income reported a high life satisfaction. This finding is in line with evidence from Beierlein, Kovaleva, László, et al. (2015), Cheung and Lucas (2015), Diener et al. (1993), Frijters et al. (2004), Pinquart and Sörensen (2000), and Sirgy et al. (1995) that the tendency to a greater self-reported life satisfaction increased with increasing income. For both nations, there were no associations between life satisfaction and age (see also Beierlein, Kovaleva, László, et al., 2015; Diener & Suh, 1998; Grevenstein & Bluemke, 2015; Heidemeier & Göritz, 2016; Sirgy et al., 1995; but unlike de Ree & Alessie, 2011) and gender (see also Beierlein, Kovaleva, László, et al., 2015; Heidemeier & Göritz, 2016; Sirgy et al., 1995; but unlike Checa et al., 2019; Grevenstein & Bluemke, 2015; Jovanović, 2019). Between life satisfaction and educational level, there was only a positive tendency (see also Grevenstein & Bluemke, 2015; Heidemeier & Göritz, 2016; Kristoffersen, 2018; Pinquart & Sörensen, 2000; Witter et al., 1984; but unlike Checa et al., 2019; Melin et al., 2003). Regarding the employment status, we found a small negative relation between life satisfaction and unemployment in the UK and a tendency in the same direction in Germany, implying lower life satisfaction for unemployed people compared to employed ones. This is in line with previous findings from Gerlach and Stephan (2001), Huschka and Wagner (2010), Knies (2010), van Suntum et al. (2010), Whiteley et al. (2010), and Winkelmann and Winkelmann (1995). Unlike Yucel (2017), who found higher life satisfaction for self-employed compared to employed respondents, and unlike Whiteley et al. (2010), who found higher life satisfaction for retired compared to employed respondents, there were no effects in the present samples but a tendency towards the opposite direction for the latter, namely, low life satisfaction for retired people or those who were doing homework.

Table 5

Correlations of L-1 with Relevant Variables

Note. UK = United Kingdom (N = 468; N_{Employment status} = 450; N_Income = 431); DE = Germany (N = 474; N_Self-esteem = 473; N_{Employment status} = 462; N_Income = 449); CI = confidence interval. Optimism–pessimism: very pessimistic (1) – very optimistic (7). Health: very bad (1) – very good (5). Gender: 1 = male, 2 = female.
^*p < .05, ^**p < .01, ^***p < .001.

Descriptive statistics

Table 6 provides the reference ranges in terms of means, standard deviations, skewness, and kurtosis of the L-1 scale score for the total population and separately for gender and age groups in both nations. Standard values are not available.

Table 6

Reference Ranges of the L-1 Scale Scores for the Total Population and Separately for Gender and Age Groups

Note. UK = United Kingdom (N = 468); DE = Germany (N = 474).

Further quality criteria

Due to its short completion time (< 10 s), the instrument can be seen as economic.

Acknowledgement

We would like to thank Melanie Partsch (GESIS – Leibniz Institute for the Social Science) for preparing the data.