IMPORTANCE OF MOTION SICKNESS 



377 



of motion siclaiess in view of Hemingway's 

 findings (40). 



Sources of Information 

 The literature on motion sickness pub- 

 lished prior to 1942 was summarized by 

 McEachem (77) and McNally (82). A 

 more recent, comprehensive, review has been 

 prepared by Tyler and Bard (114). Aside 

 from research carried on by the military- 

 services, the Subcommittee on Motion Sick- 

 ness of the National Research Council 

 sponsored research projects and published 

 a bibhography on this topic (92). A similar 

 subcommittee was organized in Canada. 

 Both of these groups have published research 

 reports and minutes of their meetings which 

 are filed with the National Research Council 

 in Washington, D. C. Several specialized 

 reviews of service-conducted research have 

 been made (2, 48, 79, 85). In addition 

 to the bibhographies of the reviews just 

 cited, a comprehensive list of titles is con- 

 tained in the bibhography on aviation medi- 

 cine (52, 53). 



Importance of Motion Sickness 

 The importance of motion sickness may 

 be judged from three types of statistics: 

 (1) the number of men disqualified for service 

 because of severe and persistent motion sick- 

 ness, (2) the incidence or number of per- 

 sonnel motion sick on one or on a group of 

 operations, and (3) the distribution of sus- 

 ceptibility to motion sickness in the 

 population. The latter distribution is in 

 a sense the percentage of persons who would 

 ever be made motion sick. 



Statistics on the incidence of motion sick- 

 ness show wide variations; although this 

 is not necessarily the result of unreliable 

 observations. Such factors as adaptation, 

 type of craft, and weather conditions all 

 have an important effect upon incidence. 



Disqualification for Military Service 

 Seasickness 



Although a considerable number of men 

 were transferred to shore duty by the United 



States Navy during World War II because 

 of intractable seasickness, no records were 

 kept of the men so transferred during the 

 early part of the war. Evidence that the 

 number of men was significant is contained 

 in the fact that several of the naval hospitals 

 in the larger ports instituted special pro- 

 cedures for examining men sent there 

 because of severe and persistent seasickness. 



A summary of Submarine War Patrol Re- 

 ports mentions seven men who were trans- 

 ferred ashore from different submarines (30) . 

 The circumstances under which these men 

 were transferred suggest that the men were 

 of little or no value to the boat. Of 1,471 

 submarine patrol reports summarized by 

 Duff, 35 reported seasickness as a problem. 



In a discussion of motion sickness prepared 

 for the Royal Australian Air Force, Mc- 

 Intyre cites no data for disqualification due 

 to seasickness, although he viewed the prob- 

 lem as of "considerable military significance" 

 (79). This lack of specific information is 

 less true of the air services because of the 

 greater opportunity to observe each man 

 during the training of flying personnel. 



Airsickness 



Available data suggest that motion sick- 

 ness was a major cause of disqualification 

 in the air forces of the Allied Nations during 

 World War II. The "washout" or "scrub" 

 rate for airsickness in pilots and air crew men 

 has been variously reported from 0.15 to 

 6.5 percent (79). Of all types of disability 

 in 2,399 cases analyzed in the South African 

 Air Forces, "... airsiclmess is the most im- 

 portant single disability . . . with the highest 

 number of permanent limitations in the air 

 crews" (95). Of 2,682 pilot trainees in the 

 RCAF, 0.5 percent were eliminated because 

 of airsickness. Navigators appear to suffer 

 a higher rate of disqualification; about five 

 percent of the potential navigators are dis- 

 qualified because of airsickness according 

 to United States and Austrahan reports (74, 

 79), and air gunners were reported to have 

 the highest rate of disqualification for air- 



