title: Observations of variable inter-observer agreement for clinical evaluation of faecal consistency in grow-finishing pigs.
abstract: Inter-observer agreement for assessment of faecal consistency in pigs was evaluated using a scoring system with 3 categories. In a pilot study, 3 observers performed an examination of faecal samples post-collection. The samples were obtained from pigs (12-13 weeks old) in 4 herds with a history of diarrhoea associated with Lawsonia intracellularis, Brachyspira spp. and/or Porcine Circovirus Type 2. Observer 1 examined all the faecal samples from the 4 herds. Observer 2 only examined the faecal samples from herds 1 and 2. Observer 3 only examined the faecal samples from herds 3 and 4. We observed a substantial agreement in faecal consistency scores between Observers 1 and 3 (kappa=0.64, 95% CI: 0.51-0.78). In contrast, only a fair agreement was observed between Observers 1 and 2 (kappa=0.24, 95% CI: 0.14-0.34). The variations in inter-observer agreement detected in the current study suggest that misclassification error can be a problem in studies assessing faecal consistency. Solutions may include developing a standardized system for scoring the consistency of pig faeces, calibration when more than one observer is involved in clinical studies and using a more objective measure of faecal consistency.
authors.affiliation: Department of Large Animal Sciences, University of Copenhagen, Groennegaardsvej 2, DK-1870 Frederiksberg C, Denmark. ken@life.ku.dk
authors.forename: Ken Steen
authors.initials: KS
authors.lastname: Pedersen
authors.forename: Patricia
authors.initials: P
authors.lastname: Holyoake
authors.forename: Helle
authors.initials: H
authors.lastname: Stege
authors.forename: Jens Peter
authors.initials: JP
authors.lastname: Nielsen
mesh_terms: D000818:Animals; D017400:Brachyspira / Q000302:isolation & purification; D018173:Circoviridae Infections / Q000453:epidemiology / Q000662:veterinary*; D017925:Circovirus / Q000302:isolation & purification; D045824:Desulfovibrionaceae Infections / Q000453:epidemiology / Q000662:veterinary*; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D005243:Feces / Q000382:microbiology*; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000662:veterinary*; D020639:Lawsonia Bacteria / Q000302:isolation & purification; D008297:Male; D015588:Observer Variation; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology* / Q000382:microbiology