The following major scientific researches investigated Medjugorje apparitions:
1. The international French-Italian scientific theological commission “on the extraordinary events that are taking place in Medjugorje” examined the apparitions of Medjugorje the most competently and the most expertly. The assembly of seventeen renowned natural scientists, doctors, psychiatrists and theologians in their research came to a conclusion on January 14, 1986 in Paina near Milan.
2. A French team of experts headed by Mr. Henri Joyeux also undertook a very serious work of examination of the visionaries. Employing the most modern equipment and expertise, it examined the internal reactions of the visionaries before, during, and after the apparitions. Likewise, the synchronization of their ocular, auditory, cardiac, and cerebral reactions. The results of that commission were very significant. They showed that the object of observation is external to the visionaries, and that any external manipulation or mutual agreement between the visionaries is excluded. The results with individual electro-encephalograms and other reactions are collected and elaborated in a special book (H. Joyeux - R. Laurentin, Etudes medicales et scientifique sur les Apparitions de Medjugorje, Paris 1986).
3. At the request of the Parish Office of Međugorje, psycho-physiological and psycho-diagnostic research was carried out on the subjects who since 1981 are known as the visionaries' group of Međugorje. The results of this research confirmed the conclusions of the international French-Italian commission and, for their part, they proved that the apparitions, to which the visionaries testify, are a phenomenon that surpasses modern science and that all points toward some other level of happening.
In regard to the scientific examination of the Medjugorje apparitions, it is important to bear in mind that in the entire history of apparitions not a single one has ever been so broadly and strictly examined scientifically as those in Medjugorje. When the examinations in Lourdes and Fatima are compared with those in Medjugorje, then there is almost no similarity whatsoever between them. Neither have other visionaries been that strictly examined nor was it possible to examine them with such certainty and success, due to the inferior level of science and the insufficiency of technical tools at that time. Besides, it is also very significant to mention that there was only one visionary in Lourdes, Bernadette Soubirous; there were three visionaries in Fatima, and six in Medjugorje. Manipulation is easier with one visionary than with several. Likewise, a group confirmation is more valuable than an individual. The said about Bernadette herself that she was psychically of delicate health. For the visionaries in Medjugorje adequate health has been established.