%0 Journal Article
%T Can We Trust the Internet to Measure Psychotic Symptoms?
%A Steffen Moritz
%A Niels Van Quaquebeke
%A Tania M. Lincoln
%A Ulf K£¿ther
%A Christina Andreou
%J Schizophrenia Research and Treatment
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/457010
%X Online studies are increasingly utilized in applied research. However, lack of external diagnostic verification in many of these investigations is seen as a threat to the reliability of the data. The present study examined the robustness of internet studies on psychosis against simulation. We compared the psychometric properties of the Community Assessment of Psychic Experiences scale (CAPE), a self-report instrument measuring psychotic symptoms, across three independent samples: (1) participants with a confirmed diagnosis of schizophrenia, (2) participants with self-reported schizophrenia who were recruited over the internet, and (3) clinical experts on schizophrenia as well as students who were asked to simulate a person with schizophrenia when completing the CAPE. The CAPE was complemented by a newly developed 4-item psychosis lie scale. Results demonstrate that experts asked to simulate schizophrenia symptoms could be distinguished from real patients: simulators overreported positive symptoms and showed elevated scores on the psychosis lie scale. The present study suggests that simulated answers in online studies on psychosis can be distinguished from authentic responses. Researchers conducting clinical online studies are advised to adopt a number of methodological precautions and to compare the psychometric properties of online studies to established clinical indices to assert the validity of their results. 1. Introduction Traditionally, psychological assessments administered by an interviewer are preferred over nonpersonal assessments such as questionnaires. Face-to-face (FTF) assessment may in some cases unveil hidden symptoms and/or partly compensate for a lack of reliable information provided by a patient alone [1]. To illustrate, a patient with psychosis may deny hearing voices upon direct questioning but at the same time be observed talking to voices without overt source. This may persuade the clinician to discard the patient's response and suspect the presence of auditory hallucinations. On the other hand, research assessing the correspondence between self- and observer ratings indicates that self-report of psychotic symptoms is more reliable than commonly thought. Studies have generally found satisfactory associations between self- and observer-based ratings for overall pathology [2], negative symptoms [3], and positive symptoms [4¨C8]. Despite the aforementioned merits, clinical assessment is not without weaknesses. The presence of an assessor may induce important biases [9, 10], especially underreporting, that are often smaller with
%U http://www.hindawi.com/journals/schizort/2013/457010/