In 1996, Hayden Ebbern, Sean Mulligan and Barry Beyerstein visited the Medical Center to investigate Clark's story. They placed a tennis shoe on the same ledge and found that it was visible from within the building and could easily have been observed by a patient lying in bed. They also discovered that the tennis shoe was easy to observe from outside the building and suggested that Maria may have overheard a comment about it during her three days in the hospital and then incorporated it into her OBE. They concluded "Maria's story merely reveals the naiveté and the power of wishful thinking" from OBE researchers seeking a paranormal explanation. Clark did not publish the description of the case until seven years after it happened, casting doubt on the story. Richard Wiseman has said that although the story is not evidence for anything paranormal it has been "endlessly repeated by writers who either couldn't be bothered to check the facts, or were unwilling to present their readers with the more skeptical side of the story."