Systematic review of declarative tactical knowledge evaluation tools based on game-play scenarios in soccer

Any sport confrontation evolves within a closed field where the actions are channeled inside the borders that space encloses in itself and, beyond this, the game has no meaning (Parlebas 1988). This closed field has a series of characteristics that distinguish and shape it, configuring the possibilities and limitations of action of the players. The way of responding to the problems that the game raises, is not only influenced by this type of constraints, but also by the players’ tactical knowledge, which is not inherent to themselves, but is developed and learned (González-Víllora et al. 2015). The players are in constant training, in continuous incorporation of knowledge and experiences, in mutual interaction with each other, and with the physical environment, enriching themselves and enriching the game (Castellano 2000). The mental images that the player must build in the course of the game, which should allow him to read and anticipate the game, are fruit, above all, of the experience, learning and training in contexts of "socio-interaction" (Casamichana et al. 2015), because in team sports, the knowledge the player needs is related to game logic (Gréhaigne et al. 1999).

In the last two decades, the analysis of tactical knowledge has become a research channel of increasing interest, contributing to the development of ad-hoc tools to carry out this task, either from the procedural or declarative level. In the sport field, procedural tactical knowledge (PTK) refers to performance and creation of movements, selecting the most adequate actions according to different competition situations (French and Thomas 1987), being intimately linked to motor action (Kirkhart 2001; Teoldo et al. 2011; Williams and Davids 1995). Specifically, in an eminently open sport with unrepeatable game-play situations such as soccer, PTK should be determined by knowing how, when and where to do it, drawing the "identity document" that determines the traits of the motor action (Parlebas 1993) and the consequences that entails for its realization (Parlebas 2001). Declarative tactical knowledge (DTK) refers to the knowledge on rules, positions, functions, basic offensive and defensive strategies, and understanding of game tactical-technical logic, “to know what to do” (Thomas et al. 1986). It is the player’s ability to declare verbally and/or in writing, what is the best decision to be made in a given training or match situation (Tenenbaum and Lidor 2005).

Traditionally, an association has been established between expertise level and declarative tactical knowledge, as it appears that high-skill players possess a larger and more elaborate declarative knowledge base (Williams and Davids 1995). For this reason, selective methodology (Anguera 2003) has traditionally been used to evaluate DTK, and numerous instruments have been designed and validated, allowing access to a large sample, quickly and directly, and with little training in its application (Salmon et al. 2009). In this wide range of instruments can be included: The questionnaires on basic knowledge, in terms of terminology, rules, principles of game and performance, used in basketball (Del Villar et al. 2004; French and Thomas 1987; Pinto 1997), volleyball (Moreno-Domínguez et al. 2006), tennis (García-González et al. 2009; McPherson 1987), soccer (Otero et al. 2012), floorball (Contreras Jordán et al. 2005), as well as invasion sports in general (Contreras Jordán et al. 2005; Figueiredo et al. 2008). Verbal protocols based on conditional statements "if …, then …", which establish that "if X occurs, then I do Y", which were used for the first time in tennis (McPherson 1987), including later in some of the works mentioned that they value tactical knowledge in other sports; as well as serving as a scaffold for the use of more sophisticated tools through static or dynamic images of game situations. Based on these verbal protocols, tennis interviews have also been conducted, which are subsequently coded according to a system of categories (García-González et al. 2006; McPherson 1999). Interviews with open questions about basic knowledge and tactical problems have been used in soccer (González-Víllora, et al. 2010a, b; Griffin et al. 2001); self-confrontation interviews (Cranach and Harré 1982) with open-ended questions, carried out after the performance of the participants themselves, have also been used in volleyball (MacQuet 2009), badminton (Macquet and Fleurance 2007), tennis (McPherson and Thomas 1989). Also, interviews through soccer video sequences have been used (Den Hartigh et al. 2018; García-López et al. 2010; González-Víllora et al. 2011, 2013; González-Víllora et al. 2010a, b; Vaeyens et al. 2007). In tennis, in-game interviews have been used to access the knowledge of the participants immediately after the action (McPherson 1987; McPherson and Thomas 1989). The ability to memorize game patterns, associated with the memory paradigm, and related in some way to the anticipatory component in team sports, and therefore to tactical knowledge, was first studied in chess (Chase and Simon 1973), having also been analyzed in soccer (Casanova et al. 2012; McMorris 1997; McMorris and Graydon 1996a, 1996b; Williams et al. 1993). Self-perception questionnaires in invasion sports (Elferink-Gemser et al. 2004) were also used in soccer (Kannekens et al. 2009; Nortje et al. 2014). Reflective supervision protocols have been used through self-reports in basketball (Iglesias 2006). Multi-response tests through iconic images of game situations have been used in soccer (De la Vega 2002; Griffin et al. 2001; McMorris and Graydon 1996a, 1996b; Quina et al. 2011; Serra-Olivares and García-López 2016) and futsal (Souza 2002). Multi-response tests through freezing images of video game sequences have been used in soccer (Bennett et al. 2019; Blomqvist et al. 2005; Fontana 2004; Giacomini et al. 2011; Keller et al. 2018; Machado and Teoldo 2020; Mangas 1999; Praça et al. 2016), tennis (Aburachid et al. 2013) and badminton (Blomqvist et al. 2000). Also, computerized tests based on situations from different sports disciplines have been used (Buscà et al. 2010), computer animations in volleyball (Broek et al. 2011), as well as game simulators in soccer (De la Vega et al. 2008; Helsen and Pauwels 1988; Sánchez-López et al. 2012). The future invites us to think that virtual reality can play a relevant role in the assessment of DTK.

Regarding the limitations found in these tools, one of the key requirements for any tool is that it must be configured from the internal logic of the game (Parlebas 1988), measuring aspects that faithfully constitute the player's soccer competence (Parlebas 2018), both in attack and defense. Furthermore, it seems interesting to go to the operational (Bayer 1979) and core/specific (Castelo 1999; Garganta and Pinto 1994; Hainaut and Benoit 1979; Kunrath et al. 2020; Machado et al. 2020; Queiroz 1983; Teoldo et al. 2009, 2011; Worthington 1974) principles of the game, as well as the roles (Lago 2000) and player subroles (Marqués et al. 2015; Obœuf et al. 2009); since they allow the analysis of the DTK from various perspectives, and in relation to the teaching-training processes. Also, an important issue present in the DTK analysis is the role of verbalization in decision-making. Decision making is defined as a choice of action, and it is a result that can be observed as a motor or verbal response (Macmahon and Mcpherson 2009). However, there is no theoretical support to defend the relationship between verbal behavior and tactical behavior (Araújo et al. 2014), so tactical skills and verbalizations about tactical skills cannot be considered equivalent (Araújo et al. 2010). This is because not everything a person says about something is everything he knows about that "something” (De la Vega 2002); since on many occasions, the human being is not able to express everything he knows through language. It is true that, explicit knowledge, in addition to allowing “to do”, also allows to explain the reasons and the processes of action (Quina et al. 2011), and verbal protocols have been used to distinguish and compare the mental processes that support the decision-making out of the context of natural play (Petiot et al. 2017), or to measure cognitive effort in perception-reflection processes (Cardoso et al. 2019). For these reasons, those instruments constructed to access DTK of the players should consider whether to use linguistic competence. Last, ensuring the validity and reliability of the data collected is important for the analysis to fulfil its intentions and purposes effectively (Tenga et al. 2009). Regarding this fact, validity and reliability are two neglected aspects in many tools contemplated in sports literature, and whose importance is essential to ensure a correct evaluation; since validity guarantees that the tool measures what it is intended to measure, while reliability confirms that the tool always measures the same.

Taking this into account, it would be necessary to know if the set of tools analyzed in this review include the above aspects, and to deepen to what extent. Therefore, the primary aim of this review is to present evaluation tools that are able to measure the DTK of soccer players through game-play scenarios without using verbal language, validly and reliably; and the secondary aims are to identify the variables studied by the tools found, evaluate their quality, find the most relevant key aspects that do not comply with the tools presented and justify the design of new tools.

The aim of this review was to present evaluation tools that are able to measure the DTK of soccer players through game-play scenarios, validly and reliably.

A total of nine tools were selected and analyzed, considering that 3 of them were not found in databases that collect studies in scientific journals, probably because these tools were validated in doctoral thesis and master's degree thesis of approximately 20 years ago, being used in subsequent studies have been published. The geographic origins of the included tools were: Spain (n = 2), Australia (n = 2), Brazil (n = 1), Portugal (n = 1), U.S.A. (n = 1), Finland (n = 1), and England (n = 1). “TacticUP video test for soccer” (Machado and Teoldo 2020) and "TCTOF" (Serra-Olivares and García-López 2016) were the tools with the highest quality score. Therefore, from this review, researchers and coaches are recommended to use these two tools compared to the other tools analyzed. Researchers are also encouraged to create and validate new tools to improve DTK analysis and evaluation based on the findings presented and organized into the following five sections: tactical variables and scores, game scenarios, validity and reliability, limitations and future perspectives.

In this systematic review, nine tools were analyzed. “TacticUP video test for soccer” (Machado and Teoldo 2020) and “TCTOF” (Serra-Olivares and García-López 2016) were the tools with the highest quality score. Most of the tools did not pass many of the criteria proposed to assess their quality. Fundamentally, it can be concluded that few tools show specific tactical scores based on game principles or subroles that allow identifying possible points of improvement in the knowledge that players have on specific aspects of the game.

For this main reason, and based on the other findings found in this review, future studies should take into account the following aspects: (i) the importance of designing tools that reflect scores based on tactical principles and game subroles, since this would allow establishing more specific teaching and training processes oriented towards the tactical component of the game, a key aspect in sociomotor sports, such as soccer; (ii) the advantages and disadvantages of designing tools based on static images or video sequences: in general, video sequences can better represent the dynamic reality of the game, but static images allow access to samples from earlier ages; (iii) the need to design tools that can access the DTK of young children (u-6, u-7, u-8); (iv) the requirement to design tools that present game-play scenarios in the first person, which is what the player can really see in the action; (v) the essentiality of facing the tools designed to rigorous processes of validity and reliability.