Launay–Slade Hallucination Scale-Extended: simplifying its interpretation

ABSTRACT

Background

The Launay–Slade Hallucination Scale – Extended (LSHS-E) is one of the most used self-reported questionnaires to explore the multidimensionality of hallucinatory-like experiences (HLEs). This scale is defined as a 5-level Likert scale, which goes from 0-“certainly does not apply to me” to 4-“certainly applies to me.” Like any Likert scale, the LSHS-E scale assumes that the ordinal categories are equally spaced among them, which might not be true, giving rise to possible issues in offering a valid interpretation of the responses.

Method

This study introduces a parametric model: the ordered stereotype model. This model determines the uneven spacing among ordinal responses, dictated by the studied data.

Results

This work shows that the ordinal categories of the LSHS-E scale are determined both by unequal spacing and by the spacing among the last three adjacent categories, which makes them indistinguishable. Subsequent analysis showed good internal reliability, and also a four-factor structure was maintained.

Discussion

The current study’s findings suggest that people who suffer from HLEs might not easily disclose their experiences and so give neutral responses for fear of being stigmatized. Further, neutral responses might identify people at risk of psychosis, and individuals during the prodromal stage may not be aware of their transient or fleeting HLEs. Future research should determine the distance among the categories on a Likert scale as a first step before analyzing and understanding the data.

KEYWORDS:

• Launay–Slade hallucination
• likert scale
• ordered stereotype model
• ordinal response
• descriptive survey study

Acknowledgments

This paper was supported by the Marsden Fund on “Dimension reduction for mixed type multivariate data” (Award Number E2987-3648) from New Zealand Government funding, administrated by the Royal Society of New Zealand to IL and DF.“Master and Back” Grant PRRMAB-A2011- 19251 from the Sardinia Region to SS.This project was financed by the Parc Sanitari Sant Joan de Déu (PSSJD: AR201404). Authors thank: Dr. Susana Ochoa, Dr Gildas Brébion for her help with the design of the study and protocol; Aida Farreny and Jorge Cuevas-Esteban for their help with data collection.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

Daniel Fernández was supported by the grant 2017 SGR 622 (GRBIO) administrated by the Departament d’Economia iConeixement de la Generalitat de Catalunya (Spain). Daniel Fernández and Ivy Liu were supported by the Marsden Grant E2987-3648 administrated by the Royal Society of New Zealand. Sara Siddi was supported by the „Master and Back„ Grant PRRMAB-A2011-19251 administrated by the Sardinian Region.