Filing Systems: Numerical Filing

Numeric filing systems are used with records that are filed and retrieved by number. Filing systems that are organized numerically require an index which correlates the patient name and numerical chart reference, which makes them an indirect access filing system (Thompson, 2018). There are three main types of numerical systems, which will be discussed below.

Consecutive Numeric/Straight Numerical

This system files consecutively numbered records in strict sequential order according to registration number; for example, the records 45677, 45678, 45679, and 45680 would be filed side-by-side. The greatest advantage of straight numerical filing systems is the ease with which staff are trained to work with them. However, there are several disadvantages to this system including:

• higher chance of misfiling as staff must consider all digits of the record number at one time when filing a record,
• the heaviest filing activity is concentrated in the area with the highest new numbers which makes it difficult for several staff to access records at the same time, and
• quality control of filing is difficult as most filing occurs in one area.  Since staff members usually file in the area of the most current records, it is not feasible to fix responsibility for a section of the file to one staff (Rajakumar, n.d.).

Terminal Digit Filing

Terminal digit filing is an adaption of consecutive numerical and was developed to distribute files evenly throughout the system, making it easier to allocate space for expansion, and overcome congestion in large filing systems when the most active records are being filed in consecutive order. In this system, the filing system is based upon the last few digits of the sequence which disperses the files throughout the system, thus allowing easier access. It is particularly valuable when working with records with long number strings (Rajakumar, n.d.; Thompson, 2018).

This system segments the number into three parts or segments, which are used as filing units. For example, record 123456 may be broken into three segments 12-34-56. Within the number, the primary digits are the last two digits, the secondary digits are the middle two, and the tertiary digits are the first two digits as shown below.

In the terminal digit filing example, the total filing area would be partitioned into 100 primary sections (00-99). Each section would then be partitioned into 100 areas, and each area would have room for 100 records. Record 12-34-56 would be filed into section 56, area 34, and would be record 12 (Thompson, 2018). Records 11-34-56 and 13-34-56 would be filed immediately before and after this record. The terminal digit method is often described using six numbers, but the length of the number can vary across systems, as will the corresponding sizes of sections, areas, and records.

When filing a number of charts in this system, the staff member would arrange files by primary, secondary and, finally, tertiary digits for ease of filing. For example, the charts 45-50-99, 44-51-99, 45-49-99, 60-49-99, and 44-50-99 would be arranged in the following order to facilitate filing. 

• 45-49-99
• 60-49-99
• 44-50-99
• 45-50-99
• 44-51-99

In the above case, the staff member is filing in section 99, and areas 49, 50 and 51. They will have their records ready to file from lowest record number to highest to assist in working through the filing in an organized manner.

Benefits

With terminal digit filing, records are equally distributed throughout the primary 100 sections of the file area—only every 100th new medical record will be filed in the same primary section, which:

• relieves congestion in active record areas where several staff are working at once,
• allows for quality control by allowing the assignment of sections for filing, for example, a staff member may be responsible for sections 00-24,
• even division of work, as the numerical numbers are still assigned in straight numerical order, for example, numbers 346371, 346372, and 346373 are assigned in strict sequence, but the records would be filed in terminal digit sections 71, 72, and 73 respectively, and
• no backshifting of records, as the addition of new records and removal of inactive records should occur at the same pace across each area (Rajakumar, n.d.).

Middle Digit Filing

In middle digit filing, the staff also files according to pairs of digits like terminal digit filing. However, the primary, secondary, and tertiary digits are in different positions. In this case, the middle set of digits are the primary digits, the digits on the left are the secondary digits, and the digits on the right are the tertiary digits (Rajakumar, n.d.).

In this example, all these charts would be filed in area 34, section 12, and by records 56, 57, and 58, respectively.

Filing in this method ensures that blocks of 100 charts are filed in straight numerical order, which can be advantageous when sampling blocks of charts for research or switching from straight numerical filing. However, this system does not provide distribution as even as in terminal digit filing, which can lead to gaps and the need for redistribution (Rajakumar, n.d.).

When filing several charts in this system, the staff member would still arrange files by primary, secondary and, finally, tertiary digits for ease of filing. For example, the charts 11-33-34, 01-33-44, 44-32-01, 11-34-00 and 10-33-43 would be arranged in the following order to facilitate filing.

• 44-32-01
• 01-33-44
• 10-33-43
• 11-33-34
• 11-34-00

In the above case, the staff member is filing in sections 32, 33 and 34. They will have their records ready to file from lowest record number to highest to assist in working through the filing in an organized manner.

References

Rajakumar, M. (n.d.). Numbering and filing system.

Thompson, V. D. (2018). Administrative and clinical procedures for the Canadian health professional (4th ed.). Pearson Canada.

Attributions

“Files” by Micah Drushal on flicker; Creative Commons – Attribution 2.0 Generic.