ABC of Medical Computing: MANIPULATING AND ANALYSING DATABMJ 1995; 311 doi: https://doi.org/10.1136/bmj.311.7005.614 (Published 02 September 1995) Cite this as: BMJ 1995;311:614
- Nicholas Lee,
- Andrew Millman
Spreadsheets form part of a family of tools for storing and manipulating numerical data. At their most basic, they perform the simple arithmetical calculations normally done on a handheld calculator. Several good programs are available that will simulate such calculators. Many of the calculator programs available provide facilities such as scientific functions, weight and measure conversions, and statistical and financial functions. They are often included in a package with other programs such as Windows or WordPerfect.
If you need to perform multiple calculations on a collection of data a spreadsheet program becomes invaluable. Spreadsheets were used before computers for bookkeeping and business accounts. However, maintaining accuracy when adding or performing the calculations on the figures within a spreadsheet was always a problem. A computer spreadsheet overcomes this problem. The calculations are always accurate, and if you make an alteration in a massive spreadsheet, the hundreds of calculations required to update the figures and totals are done in seconds.
Structure of spreadsheets
A spreadsheet consists of columns labelled on the top A, B, C, D … and rows labelled on the left 1, 2, 3, 4…. The cells within the table are identified by the column and row label--for example, A1, A2, B1, B2. The column letter always goes first. You can enter numbers, formulas, or words into the cells. Entering a formula instructs the spreadsheet to carry out a calculation on data in other cells. For example, to add all the numbers in a column you would enter the formula B1+B2+B3+B5+B6+B7 into the cell you wish the total to be placed or more simply use the summing function. If any of the numbers are altered the spreadsheet automatically recalculates the total.