sustainability Article Validation of a Football Competence Observation System (FOCOS), Linked to Procedural Tactical Knowledge Rubén Sánchez-López * , Ibon Echeazarra and Julen Castellano Department of Physical Education and Sport, University of the Basque Country (UPV/EHU), 01007 Vitoria-Gasteiz, Spain;
[email protected] (I.E.);
[email protected] (J.C.) * Correspondence:
[email protected] Abstract: The use of instruments for the evaluation of a player’s procedural tactical knowledge (PTK) in sociomotor sports, such as football, is a line of research of growing interest since it allows a pertinent description of the player’s football competence. The aim of this study is to configure and validate an ad-hoc observational tool that allows evaluating the player’s PTK, understood as football competence, from the observation, coding and recording of the roles, the actions of the acquired subroles and the operational and specific principles of football in the attack and defense phases. Based on the Delphi method, a field format coding instrument was designed and validated where each criterion is a system of categories, exhaustive and mutually exclusive. The results showed excellent content validity (9.02 out of 10), and high values of intra-observer stability (k = 0.747) and inter-observer agreement (k = 0.665). Generalizability analysis showed an excellent reliability (G = 0.99). Additionally, the construct validity of the tool was calculated through a small-sided game Gk + 4v4 + Gk, using two independent samples: semi-professional and amateur players. The results reflected significant differences (α < 0.05) between both samples in the variables total score, offensive score and defensive score.