one reference standard, and contact could not be established with the author Spangler 1998 The published paper suggests that data were collected on at least one index test (fluid intake), Martof 1997 Rikkert 1997 The published paper suggests that data were collected on a reference standard (serum osmolali-Authors replied that datasets have been lost in computer upgrades however it was not clear whether data were collected on at least one reference standard. The au- ty and weight change) and at least one index test (fluid balance, fluid intake, urine volume, sunken thors suggested that no reference standard was collected, but did not confirm this Roberts 1991 eyes, dry mucous membranes, tenting), however data are not in a format that can be used for this Sugaya 2008 review and contact could not be established with author It appears that the dataset includes a reference standard (serum osmolality) and index tests (urine osmolality) but not in a format that can be utilised in the review, and no dataset received as con- Mentes 2003 Authors state that they did not collect any reference standard data tact could not be established with the authors Mentes 2008 Suhr 2004 Saliva osmolality collected, but no reference standard measured Authors confirmed that they did not collect data on serum osmolality, short term weight change or serum data that would allow calculation of serum osmolarity Meuleman 1992 Authors state that they no longer have access to the dataset Suhr 2010 Authors confirmed that they did not collect data on serum osmolality, short term weight change or Morgan 2002 The published paper suggests that data were collected on a reference standard (serum osmolality) serum data that would allow calculation of serum osmolarity and at least one index test (heart rate), however data are not in a format that can be used for this Szewczyk 2008 review and contact could not be established with author Morgan 2003 Rosher 2004 The published paper suggests that data were collected on a reference standard (serum osmolali-It appears that the dataset includes a reference standard (weight change) and index tests (BIA as- ty) and at least one index test (urine osmolality, USG), however data are not in a format that can be sessment of TBW, ECW, foot vein filling, skin turgor, dry mucous membranes, sunken eyes, tongue used for this review and contact could not be established with author furrows, pulse rate) but not in a format that can be utilised in the review, and no contact could be established with researchers Norman 2007 The published paper suggests that data were collected on at least one index test (BIA assessment Rosler 2010 of TBW), however it was not clear whether data were collected on at least one reference standard, Authors confirmed that they did not collect data on serum osmolality, short term weight change or and contact could not be established with the author serum data that would allow calculation of serum osmolarity O'Neill 1992 Rudolph 2011 Authors replied that they no longer have access to the dataset Authors replied that they did not collect any data we could use as a reference standard (no serum osmolality or components of osmolarity) O'Neill 1997 Authors replied that they no longer have access to the dataset Savalle 2012 Corresponding author replied to say that no reference standard was collected Olde Rikkert 1997 Authors replied that datasets have been lost in computer upgrades Schols 1991 Authors replied that the data were gathered too long ago to be recollected Olde Rikkert 1998 Authors replied that datasets have been lost in computer upgrades Schut 2005 It appears that the dataset includes a reference standard (plasma osmolality) and index tests (BIA Johnson 1994 Palevsky 1996 The first author replied to our query and stated that the raw data for his study had not been kept, and are no longer available assessment of TBW, dry tongue, tongue furrows, thirst perception, heart rate, orthostatic hypoten-Authors confirmed that they did not collect data on serum osmolality, short term weight change or sion, dry mucous membranes) but not in a format that can be utilised in the review, and no dataset serum data that would allow calculation of serum osmolarity received (researcher stated he was ill and would consider this when he recovered) Kayser-Jones 1999 Perrier 2013 Seinela 2003 Phillips 1984 Participants were aged 25 to 40 years, none were aged ≥ 65 years Authors confirmed that they did not collect data on serum osmolality, short term weight change or Authors confirmed that they did not collect data on serum osmolality, short term weight change or serum data that would allow calculation of serum osmolarity Professor Rolls posted us the PhD thesis that this paper was based on, but unfortunately it did not serum data that would allow calculation of serum osmolarity Kehayias 2012 Shim 1987 Author confirmed that they did not collect reference standard data contain enough detail for us to create 2x2 tables (for serum osmolality versus.