The definition of culture

The term “culture” is extremely difficult to define, which has led to a large proliferation of definitions. Most scholars consider culture as a set of habits, values, beliefs, and practices that members of a distinct society use to interact with each other and which are learned, acquired, and transmitted through symbols, institutions, and technologies. Culture may be defined at the level of an entire society (eg, referring to a group of individuals with common nationality) but also on the level of distinct groups within any society (eg, referring to a group of individuals with common religious beliefs). The term “culture” is often used erroneously in the context of race (referring to a group of individuals with the same physical characteristics, for example skin color) or when being assigned to minority populations, or is even sometimes used as a causal factor for a disorder. Despite the difficulties to define the word “culture” there seems consensus that “culture emerges in adaptive interactions between humans and environment, consists of shared elements between individuals and is transmitted across time periods and generations.”

Jenni and O’Connor have adopted David Hufford’s view that “culture is the entire non-biological inheritance of human beings.” In other words, everything that human beings inherit from one generation to the next that is not passed on biologically is a part of culture. To put it simply: “if you got it from other human beings and you didn’t get it through biology, then you got it through culture.” We are all included in this broad definition of culture: culture is not something that comes through the door with patients. It means that not only values, languages, religions, arts, cuisines, modes of dress, family structures, authority relationships, gender roles, social behavioral norms, and modes of communication are elements of culture, but also economic and political structures, sciences, modern information technologies, bodies of knowledge and texts, reference works, and health care resources. All are products of culture, and all reflect cultural shaping.

There are many cultural differences that may be described in multiple dimensions. As a typical example, cultures may be distinguished on the basis of their individualism/collectivism or independency/interdependency dimension (although this classification is rather simplistic because not all members of a culture may share the same tendencies and behave in different manner ). Individualism refers to when individuals view themselves as separate and autonomous from each other, whereas collectivism refers to when individuals view themselves as interconnected and defined by their relations and social context. Asian countries predominantly rely on collectivism, whereas Euroamerican (Caucasian) countries rely on individualism. Cultural differences or cultural standards may also be described in the dimension of uncertainty avoidance (to which extent rules are used to live together) or power distance (how it is expected that power is equally or unequally distributed). Cultural standards always indicate how members of a specific culture should behave and how objects and actions should be valued and coped with. It is important to bear in mind, however, that all cultures are partial, in the sense that they select for certain human preferences and omit (or never even imagine) others. In addition, while cultures provide some guidelines for regulating human behavior, in reality there are considerable individual differences in the behavior within a culture.

Cross-cultural comparative aspects

Cross-cultural comparative research among societies of different political, economic, and ideological backgrounds is a straightforward approach for the study of the roles of culture on sleep behavior and its interpretation. Previous studies have primarily focused on key aspects of sleep behavior: sleep duration and sleep need; bedtime routines; napping; children’s use of sleep aids; sleeping arrangements, particularly cosleeping of children and parents; sleep problems including bedtime resistance, nighttime awakenings, and sleep terrors. For detailed information the reader is referred to previous work.

However, do the variations in sleep behavior across cultures reflect the true cultural differences or rather differences based on the methodology used? The scientific pediatric sleep literature cited in previous articles illustrates some of the inherent difficulties in comparative and cross-cultural research. For example, studies within and across countries and cultures have used different recruitment strategies (eg, population randomly selected from national surveys or from clinical, urban, or rural populations), and have examined different numbers of subjects and descriptions of age ranges. In addition, the variation of reported sleep behavior across decades limits comparability between studies performed at different times. Problems in cross-cultural research particularly arise in the attempt to compare studies of cultural groups conducted with instruments (eg, questionnaires sent by mail or filled out in the pediatrician’s office, or face-to-face or telephone interviews) that have not been cross-culturally standardized, appropriately translated, or validated for the populations under study (see also Sagheri and colleagues ).

Another problem lies in the numerous definitions of key terms. For example, “sleep amount,” “sleep need,” “sleep duration,” and “time in bed” are terms that often are used interchangeably in the literature. Apart from the obvious problem that “time in bed” may be different from actual sleep time and thus is not a reliable proxy for “sleep amount or duration,” these common research terms may have different conceptual meanings across the cultures in which the studies were conducted. In a substantial number of studies, sleep behavior and practices have not been assessed with appropriate validated instruments or qualitative inquiry. Rather, general cultural influences have been assumed or inferred according to the investigators’ own (often tacit) guiding assumptions.

True cross-cultural comparative studies of children’s sleep behavior are extremely rare. There is currently only one large-scale survey available that describes parent-reported sleep patterns and behaviors, sleep problems, and sleeping arrangements of children using the same method in 17 Caucasian and Asian countries. If we bear in mind that countries should not be equated with culture (because of the large cultural heterogeneity that exists within any country), this Internet-based study by Mindell and colleagues shows that infants and toddlers in Asian countries may obtain less overall sleep, have later bedtimes, are more likely to room-share, and are perceived to have more sleep problems than children of the same age in Caucasian countries. However, the investigators may not answer the question as to whether these variations reflect true differences in children’s sleep behavior or rather indicate culturally driven reporting biases. Individuals living in diverse cultural value systems may demonstrate different types of response biases when completing behavioral surveys. Thus, objective methods for assessing sleep behavior should be included in future cross-cultural studies. By the comparison of agreement rates between objective measures and subjective reports of different cultures, the reporting biases may be operationalized and described. It is interesting that the study by Mindell and colleagues also indicates that not all aspects of sleep are influenced by cultural beliefs and practices to the same extent: daytime sleep seems to be less likely influenced than nocturnal sleep, which may point to a strong biological drive for sleeping during the day.

Cross-cultural comparative aspects

Cross-cultural comparative research among societies of different political, economic, and ideological backgrounds is a straightforward approach for the study of the roles of culture on sleep behavior and its interpretation. Previous studies have primarily focused on key aspects of sleep behavior: sleep duration and sleep need; bedtime routines; napping; children’s use of sleep aids; sleeping arrangements, particularly cosleeping of children and parents; sleep problems including bedtime resistance, nighttime awakenings, and sleep terrors. For detailed information the reader is referred to previous work.

However, do the variations in sleep behavior across cultures reflect the true cultural differences or rather differences based on the methodology used? The scientific pediatric sleep literature cited in previous articles illustrates some of the inherent difficulties in comparative and cross-cultural research. For example, studies within and across countries and cultures have used different recruitment strategies (eg, population randomly selected from national surveys or from clinical, urban, or rural populations), and have examined different numbers of subjects and descriptions of age ranges. In addition, the variation of reported sleep behavior across decades limits comparability between studies performed at different times. Problems in cross-cultural research particularly arise in the attempt to compare studies of cultural groups conducted with instruments (eg, questionnaires sent by mail or filled out in the pediatrician’s office, or face-to-face or telephone interviews) that have not been cross-culturally standardized, appropriately translated, or validated for the populations under study (see also Sagheri and colleagues ).

Another problem lies in the numerous definitions of key terms. For example, “sleep amount,” “sleep need,” “sleep duration,” and “time in bed” are terms that often are used interchangeably in the literature. Apart from the obvious problem that “time in bed” may be different from actual sleep time and thus is not a reliable proxy for “sleep amount or duration,” these common research terms may have different conceptual meanings across the cultures in which the studies were conducted. In a substantial number of studies, sleep behavior and practices have not been assessed with appropriate validated instruments or qualitative inquiry. Rather, general cultural influences have been assumed or inferred according to the investigators’ own (often tacit) guiding assumptions.

True cross-cultural comparative studies of children’s sleep behavior are extremely rare. There is currently only one large-scale survey available that describes parent-reported sleep patterns and behaviors, sleep problems, and sleeping arrangements of children using the same method in 17 Caucasian and Asian countries. If we bear in mind that countries should not be equated with culture (because of the large cultural heterogeneity that exists within any country), this Internet-based study by Mindell and colleagues shows that infants and toddlers in Asian countries may obtain less overall sleep, have later bedtimes, are more likely to room-share, and are perceived to have more sleep problems than children of the same age in Caucasian countries. However, the investigators may not answer the question as to whether these variations reflect true differences in children’s sleep behavior or rather indicate culturally driven reporting biases. Individuals living in diverse cultural value systems may demonstrate different types of response biases when completing behavioral surveys. Thus, objective methods for assessing sleep behavior should be included in future cross-cultural studies. By the comparison of agreement rates between objective measures and subjective reports of different cultures, the reporting biases may be operationalized and described. It is interesting that the study by Mindell and colleagues also indicates that not all aspects of sleep are influenced by cultural beliefs and practices to the same extent: daytime sleep seems to be less likely influenced than nocturnal sleep, which may point to a strong biological drive for sleeping during the day.