Traditional methods for quantifying sport performances (e.g., frequency of actions) are limited in their ability to describe the interaction of events that occur over time (Borrie et al., 2002). The aim of our study was to develop an innovative instrument for observation that can strengthen the existing schemes of game analysis in football in order to provide specific additional information on the behavior of Goalkeepers (GK) during the Defensive Process (DP). The observational design of this study is located in quadrant IV, i.e. it has got a Follow-up design/Nomothetic/multidimensional (Anguera et al., 2000). The observational instrument is formed by a combination of field format and systems of categories. Our research focused on binomial Finalization/GK or attempted Finalization/GK, and investigated what precedes the finalization and what happens to the completion of the GK intervention. The games were recorded on VHS video and then converted to MPEG-1. Our decision in relation to the observational sample took into account the establishment of 2 sampling levels (intersessional and intrasessional), from which a series of measures were taken. After a series of experimental observational sessions to test the observational instrument and to train the observers, we analyzed the quality of data through the intra-observer agreement (verified by the Kappa index of reliability of Cohen). The comparison of data recorded during the observational period was done using the SDIS-GSEQ program and its function for "calculating the Kappa coefficient". The resultant observational instrument `ad hoc` was created according to four criteria: i) guiding the offensive process; ii) offensive end of the process; iii) GK in the defensive process; and iv) effectiveness of the GK in the defensive process. The instrument of codification was sufficiently discriminatory; therefore fulfilling the requirements for the purpose it was created. It also demonstrated to be highly reliable, seen by the high correlation values (over 97,5 % for all criteria), and therefore opening the possibility for more objectives studies. This instrument may be improved in the future by adapting it to the specific aims of the investigation and knowing that one can add or delete criteria, or simply focus on specific aspects of interest in studying certain football match periods.
© Copyright 2009 14th annual Congress of the European College of Sport Science, Oslo/Norway, June 24-27, 2009, Book of Abstracts. Veröffentlicht von The Norwegian School of Sport Sciences. Alle Rechte vorbehalten.