The observation is based on the ability perception and decision of the human being. There is ordinary observation, which constitutes an important source of information in everyday life, and scientific observation, which provides objective, valid and reliable knowledge to answer a research question.
The reliability of the observational method refers to the quality control of the data that informs us if there is a coincidence in the judgments made by the same observer in the same observation situation but at two different times or by two different observers who independently face the same observation situation. observation.
Categorization of Observational Methodology
Scientific observation is a way of capturing reality that can be applied with rigor and systematicity, and that ultimately makes it possible to collect relevant information in a scientific study. The contribution of observation to the methodology of scientific research is double:
- As a data collection technique: it can be involved in any type of research design. For example, it can be the way to measure the VD of any design.
- As an observational method: it is characterized by the researcher’s non-intervention in the study phenomenon and by the non-restriction of the subjects’ responses through the tasks or evaluation instruments.
- The observational method is defined as a modality of the scientific method that, through the systematic and objective recording of behavior that is generated spontaneously, allows the testing of hypotheses, the replicability of its results and contributes to theoretical development by providing valid results in a field. specific knowledge.
- The use of observation in scientific research has to do with the degree of structuring of the observation and the degree of participation of the observer.
Degrees of structuring of observation
Naturalistic observation: when the behavior of the subjects is observed naturally, in their usual environment or context, and without any type of modification by the researcher. Semi-structured observation: when the researcher introduces some type of modification in the observation situation, in order to guarantee the manifestation of the behaviors of interest or constant elements that allow subsequent comparisons. Structured observation: when the researcher systematically intervenes or makes substantial modifications in the observation situation. The behavior to be observed is no longer generated spontaneously, but can be an effect of the researcher’s intervention.
Degrees of observer participation
Non-participant or external observation: it is characterized because the observer does not integrate into the situation that is being observed. Participant observation: the observer is part of the observation situation itself by participating in the activities that are being observed. Participant as observer or observation by close friends: a natural member of the group or situation under study is the one who performs the functions of observer. Self-observation: it is the subject under study himself who records his behavior.
Research planning
Common aspects with any research: Identification of the problem and formation of hypotheses. Design (Procedural decisions). Data collection: registration and coding. Data quality control: validity and reliability. Data analysis and interpretation of results.
Particular procedures of the observational method:
- What to watch: is resolved through the choice, adaptation or creation of the category system (it determines, through its internal structure and in the definition of its categories, the behaviors that are relevant to the problem of study and that therefore must be recorded by the observer).
- Who, when, where and how much to observe: decisions that are resolved by a sampling procedure. In this strategy it is necessary to guarantee the relevance and representativeness of the sample. To do this, the following are planned: the number of observation sessions, their start and end criteria, when, where they will be observed (intersession sampling) and who will be the subjects observed in each session (intra-session sampling).
- How to observe: form of recording the data and properties of the behavior that will be taken into account as a source of information (occurrence and/or duration and/or order of appearance).
Measurement and measurement scales of the observational method
The researcher observes and records with a sample of the behavior of the individual or group under study, which must reflect its characteristics and real dynamics. That is, the sample must be representative. The representativeness of the sample will depend fundamentally on: The sampling rules chosen or decided for the investigation. The registration rules specific. Clarification of two concepts:
- Observation session: continuous period of time during which the observer systematically records the behaviors under study.
- Observation period: total period of time in which it would make sense to record the subject’s behavior based on the objectives of the study.
Sampling rules
Once the problem has been defined, the study sample is selected, which must be representative of the population. Intra-session sampling rules (choosing which subjects will be observed and when within each observation session): Focal subject sampling: This rule indicates that a single subject (or sampling unit) becomes the focus of the observer’s sustained attention. .
Scanning or multifocal sampling: The observer focuses on each of the individuals in very short periods of time, going from one subject to another, in an established order that is repeated several times in the session. Combined sampling (focal subject and scan): The observer focuses on a single focal individual, and every certain period of time performs a complete scan of all group members and then returns to his or her focal subject. Intersessional sampling rules (establish start and end criteria for observation sessions): Fixed selection: a fixed and limited criterion is applied.
Simple random sampling: The criteria are selected randomly. Stratified random sampling: random selection of criteria from each of the available strata or groups. Systematic random sampling: the start time of the first session is selected at random and, from this, a systematic rule is applied to start the following sessions, taking into account the duration of the sessions and/or the distance between them.
Registration rules
The observational record consists of the notes made of the observed behavior. Frequently these annotations are made through codes that represent each of the categories of the system (coding). Recording activated by transitions (RAT): Recording rule that determines the annotation of all occurrences of the relevant behaviors (event record) and with information on their duration (state record).
It is called this because it reflects that the “activation” of the observer to perform a new registration movement occurs with each change or transition in the behavior of the observed subject.
Register activated by units of time (RAUT): Recording rule that imposes on the observer a recording pattern determined by periods of time. Either the specific temporal moments are identified in which what is happening is recorded, through the categories (punctual or snapshot sampling), or the session is divided into short consecutive periods and at the end of each the categories are recorded. of behavior that have occurred during it (interval sampling).
Reliability and validity
Reliability by consensus is the progressive adjustment of the records of two or more observers (often one of them is the researcher) that is carried out through joint and negotiated work in the application of the category system in some observation sessions. . It is usually part of the observer’s preparation process and also serves to test and refine the category system.
Sources of error and forms of control in observation
The study subject as a source of error: reactivity Reactivity is the name given to the changes that occur, voluntarily or involuntarily, in subjects due to the simple fact of feeling observed. Factors that influence reactivity are: the visibility of the observer and certain qualities of the observer.
The observer as a source of error The observer can be a source of error in the study data due to the application of the category system, due to inadequate interpretation of the categories or errors in recording due to lack of attention to certain elements. Let’s look at some of these errors:
- Observer drift: Your own experience can lead you to develop personal interpretations and adaptations of the original definitions of the categories, systematically deviating from them in the recording of data.
- Observer expectations: or expectations of what should happen or appear in the situation studied, altering the behaviors to be recorded. A control strategy is the blind procedure (the observer does not know the objective and hypothesis of the study).
The system of categories and codes
Problems with the definition of categories, excessive breadth or complexity of the system or the application of arbitrary codes, too far from the meaning of the categories, are also sources of errors.
Agreement rates
Percentage of agreement: expresses, in terms of percentage, the comparison of the records of the two observers and the count of the recorded occurrences of behavior in which they coincide (Number Agreements), to divide it by the total of events recorded (Number Agreements + Number of Disagreements).
(P = (No. Agreements) / (No. Agreements + No. Disagreements)x 100)
Kappa index (Cohen, 1960): expresses the proportion between actual agreements and possible agreements corrected by subtracting the agreements due to chance. (K = Po – Pe) / (1 – Pe) x 100)
Data design and analysis
The statistical techniques applicable for data analysis will vary depending on the type of observational study proposed and it is, ultimately, the specific objectives of the research that determine the structure of the study and the procedural decisions consistent with it. Let’s look at the different data analysis possibilities:
- According to the objectives of the analysis: Exploratory analysis: analysis of specific relationships to find significant presences or relationships.
- Confirmatory analysis: verification and contrast of hypotheses or predictions.
- Depending on the inclusion of the time variable: Synchronous analysis: when measures that have been taken simultaneously are described and related.
- Synchronous analysis: when measures that have…