[1] Karlis' first research, conducted in the 1940s, was inspired by the work of English physicist and parapsychologist William F. Barrett, specifically his book, Death Bed Visions.

[citation needed] In an attempt to build on Barrett's research, he and Erlendur Haraldsson conducted a four-year study whereby they sent out hundreds of questionnaires to doctors and nurses in both the US and northern India, asking them about their observations regarding dying patients.

He would attempt to leave his body to a shielded chamber to identify a target that contained strain gauges to detect mechanical activity.

Osis' conclusion therefore seems quite unjustified and the results do not unambiguously support the idea that Alex Tanous was able to influence the strain gauges with his OBE presence.

Magician Milbourne Christopher has written that none of Osis' "out-of-the-body experiments can be properly evaluated; complete data about them have never been published.

[12] According to Terence Hines: Osis and Haraldsson's (1977) study was based on replies received from ten thousand questionnaires sent to doctors and nurses in the United States and India.

This means they had passed through two highly fallible and constructive human memory systems (the doctor's or nurse's and the actual patient's) before reaching Osis and Haraldsson.