<ch45 toc ch47>

46 Data entry forms and screens

46.1 Purpose
46.2 Strengths, weaknesses, and limitations
46.3 Inputs and related ideas
46.4 Concepts
46.4.1 Data capture and data entry
46.4.2 Designing forms
46.4.3 Designing screens
46.4.4 Input controls
46.5 Key terms
46.6 Software
46.7 References

46.1 Purpose

A form is a document (or a simulated document on a screen) that is used to capture data. This # discusses several basic form design and screen design principles and identifies some input controls that can be used to screen input data.

46.2 Strengths, weaknesses, and limitations

Paper forms are extremely flexible. They can be carried virtually anywhere and completed using such simple technology as a pen or a pencil. Except for running out of forms or ink, they are not subject to failure. However, the data recorded on a paper form must subsequently be entered into a computer through a keyboard, a scanner, or similar equipment. Because the data capture and data entry steps are separated by time, the data might not be available in a timely fashion, and the process of obtaining the feedback needed to correct errors is lengthy and complex.

Although laptop computers are quite portable, screens generally require the user to stay near a source of electrical power and to avoid certain environments, and a screen can fail. (Field personnel sometimes carry an appropriate set of paper forms as a backup.) However, because a screen is directly linked to a computer, the data can be utilized as soon as they are entered (thus enhancing timeliness) and verified and corrected interactively (thus enhancing data accuracy).

46.3 Inputs and related ideas

Forms and screens are important parts of the user interface (# 48). The contents of a given form or screen can often be derived from the logical data structures identified during the analysis stage of the system development life cycle by using such tools as data flow diagrams (# 24), prototypes (#s 31 and 32), and Warnier-Orr diagrams (# 33). The data are typically documented in the data dictionary (# 25), and important form and screen design criteria can often be found in the requirements specification (# 35). At the high-level physical design stage, symbols on the system flowchart (# 37) identify necessary screens and forms. Prototyping (# 31) and rapid application design (# 32) are useful tools for designing forms and screens.

Related concepts include survey instruments (# 17), report design (# 47), user interface design (# 48), dialogue design (# 49), windows design (# 50), web page design and hyperlinks (# 51), and system controls (# 77). The contents of forms and screens are an important source of information about the existing system during the problem definition and information gathering stage (Part II) of a subsequent system development life cycle.

46.4 Concepts

A form is a document (or a simulated document on a screen) that is used to capture data. This # discusses several basic form design and screen design principles and identifies some input controls that can be used to screen input data.

46.4.1 Data capture and data entry

As the term implies, data capture is the process of initially capturing source data. Data entry, in contrast, is the process of converting the source data into a machine-readable form and entering the data into a computer.

In a batch environment, data capture and data entry are sometimes viewed as separate steps. First, the data are captured on paper or some other medium and collected over time. Then the data are entered using such equipment as a keyboard, a MICR reader, an optical character recognition (OCR) scanner, a regular scanner with OCR software, a mark sense reader, and so on.

In an on-line or interactive environment, data capture and data entry are combined in a single step. For example, when a customer uses an ATM machine to perform a banking transaction, the data are captured in electronic form and immediately processed, eliminating the need for a subsequent data entry step.

46.4.2 Designing forms

Many applications call for forms; for example, Figure 46.1 shows a sales receipt (or sales invoice) form. Forms are used to capture source data, and the forms themselves are sometimes retained in long-term storage. Completed forms can be scanned or the data can be input to a computer through a keyboard. Alternatively, a form image can be displayed on a screen and used as a template for on-line or interactive data entry.


Figure 46.1  An invoice form.

Form design is an art, but a few simple guidelines can help. The starting point is the necessary data. Analyze the appropriate data flow diagrams, data dictionary entries, data structures, requirements, and other analysis documentation and identify all the data elements or fields that must appear on the form.

A key consideration in designing a form is anticipating how the user is likely to scan the form. In Western societies, people read from left to right, starting at the top left and preceding down the page. Consequently, users naturally look first at the upper left of a document and follow a left to right and top to bottom pattern from the starting point. A well-designed form takes advantage of that natural tendency. For example, the invoice pictured in Figure 46.1 features a prominent logo at the upper left (the starting point), positions customer information (the first data to be entered) to the right of the logo, and then provides a series of lines for entering the item purchased data. Notice how the lines and boxes tend to guide the eye and suggest the proper order for entering data values.

A second primary objective is to make sure the form itself does not introduce errors. Allow enough space for each field. Although it is tempting to try to avoid the need for a second form, jamming too much information on a single page virtually guarantees that important data will be missed or recorded incorrectly. Clearly distinguish captions, directions, and other supporting information from the data. For example, set the supporting information in a unique font or color that cannot possibly be mistaken for source data. The preprinted invoice number on Figure 46.1 is another good example; note that it is set in a font that clearly distinguishes it from the preprinted captions. Finally, avoid the temptation to overdo fonts, colors, graphics, and special effects. The focus should be on the data, not the form.

A well-designed form can help to enhance data accuracy. For example, related fields should be entered together. Proximity implies association, so use lines, boxes, color, and white space to group related fields and to visually separate the groups. Group fields (or attributes) that are associated with the same entity; for example, the customer’s name, address, and telephone number are grouped in a box at the top right of Figure 46.1 and the data associated with sales are grouped in the lower box. Consider the source of each field and group fields from the same source. Anticipate the order in which the user is likely to enter the data and try to follow that natural order (e.g., name first, then street address, then city, etc.).

Provide clear, unambiguous directions and captions, and include examples where appropriate. Some fields call for free-form data recording; the lines for entering customer data on Figure 46.1 are good examples. Sometimes, single-character blocks or (lightly) printed examples or templates show the user exactly where and how to record the values for specific fields. Blocks are particularly useful for fixed length fields (Figure 46.2). Templates are particularly useful for numeric only or character only fields. Check lists are also popular; the available choices are listed on the form and the user selects an entry by marking it in some way or clicking on a box (Figure 46.3, lower right). It is not unusual for a given form to incorporate different data recording techniques for different fields.

Common or “standard” forms can be purchased from most office supply stores, and many form design software packages include libraries of sample forms and form templates that can be customized.

46.4.3 Designing screens

A screen can be used to display a report or to electronically simulate a form, but more dynamic images can be displayed, too. Like form design, screen design is a bit of an art, but once again a few simple guidelines can help.

The principles of form design still apply to screen design. The starting point is the necessary data. People still read a screen from left to right and from top to bottom. The screen itself must not introduce errors, so allow enough space for each field and clearly distinguish captions, directions, and other supporting information from the data. Use lines, boxes, color, and white space to group related fields and to visually separate the groups. Provide clear, unambiguous directions and captions, and provide examples where appropriate.


Figure 46.2  A screen for entering a date and a customer code.


Figure 46.3  A screen for entering an item purchased.

Design for the user. Get the user involved in the process by prototyping the screens. Take advantage of what the user already knows by simulating existing forms and reports on the screen and by following the conventions of applications the user already knows. Always provide feedback; following any transaction or operation, tell the user what happened. Never leave the user hanging. As a minimum, provide features to support easy recovery from errors and to facilitate backward migration. For example, allow the user to back up one screen by pressing the escape key.

Extend the idea of grouping related fields by designing a set of related screens so that each screen supports a complete operation or a complete set of related operations. For example, consider using one screen to collect customer data (Figure 46.2) and another screen to collect item purchased data (Figure 46.3), and so on. When data must be entered through a set of related screens, be consistent. Use the same conventions on all parts of the screen and on all screens.

Unlike paper forms, screens support numerous features (such as color changes, font changes, reverse video, blinking characters, variable lines, boxes, shapes, graphics, and animation) that can be used to dynamically capture the user’s attention or communicate information. For example, graying out or ghosting unavailable options can help to avoid confusion, and blinking a field, displaying it in reverse video, or pointing to it with an animated arrow can call the user’s attention to a data entry error. (People notice things that move, change, or are different.) Avoid adding special features just because they are technically feasible (or just to show off), however.

Monitor capability is an important factor in determining what can be displayed on a screen. For example, resolution, the level of detail a screen can show, is a function of the number of pixels (or dots) on the screen. A CGA (Color/Graphics Adapter) monitor supports low-resolution (640 × 200 pixels, 2 color or 320 × 200 pixels, 4 color) graphics. The VGA (Video Graphics Array) standard supports higher resolutions (640 × 480, 256 colors), and superVGA (SVGA) increases the resolution to at least 800 × 600 pixels and makes more colors available. An XGA (extended graphics array) monitor supports 1024 × 768 pixels. A detailed discussion of the related hardware concepts is beyond the scope of this course.

Traditionally, screens are used to display output, echoing the characters typed through a keyboard or displaying selected data stored in memory, but new technology makes it possible to use a screen as an input device. Hyperlinked screens are used to support graphic presentation such as a slide show, with the hyperlinks controlling slide sequence. An icon input screen allows the user to trigger the execution of a related routine by clicking on an icon. Finally, a graphic input screen, or touch screen, allows a user to input a command or request information by pointing; the touch screens in shopping mall kiosks are a good example.

Screen design tools are often incorporated in prototyping and CASE software.

46.4.4 Input controls

The objective of input controls is to screen out and (if possible) correct bad data before they enter the system. Validity tests are used to ensure that each input field is the right type (numeric, alphabetic), that the value of a given field is within upper and lower bounds, that fixed length fields (e.g., social security number, telephone number) are the right length, and so on. Exception tests are used to screen such “exceptional” values as a zero in a field that will be used as a divisor. Reasonableness tests are used to screen invalid values (e.g., anything but F or M in a single-character sex or gender field).

Input controls are implemented at data entry time. If the data capture and data entry steps are separated by time, the input controls are used to flag erroneous transactions for subsequent review. In some cases, the bad transactions can be corrected in time for processing with the current batch. In other cases, the flagged transactions are corrected off-line and must wait until the next scheduled batch run. However, if the data collection and data entry steps are combined in an on-line, interactive system, errors can be identified and corrected as they are entered.

46.5 Key terms

Data capture —
The process of initially capturing source data.
Data entry —
The process of converting source data into a machine-readable form and entering them into a computer.
Exception test —
A test used to screen such exceptional values as a zero in a field that will be used as a divisor.
Form —
A paper document (or a simulated document on a screen) that is used to capture data.
Graphic input screen (touch screen) —
A screen that allows a user to input a command or request information by pointing.
Hyperlinked screens —
A set of screens connected by hyperlinks; for example, in a slide show presentation, hyperlinks are used to control slide sequence.
Icon input screen —
An input screen that allows the user to trigger the execution of a related routine by clicking on an icon.
Input control —
A test or control, designed to screen out and (if possible) correct bad data before they enter the system.
Pixel —
A picture element; a dot on a screen.
Reasonableness test —
A test used to screen invalid values (e.g., anything but F or M in a single-character sex or gender field).
Resolution —
The level of detail a screen can show, a function of the number of pixels (or dots) on the screen.
Screen (display screen) —
An output device that resembles a television screen.
Source data —
The original data that describe a transaction.
Validity test —
A test used to ensure that each input field is the right type (numeric, alphabetic), that the value of a given field is within upper and lower bounds, that fixed length fields (e.g., social security number, telephone number) are the right length, and so on.
White space —
Space on a form or a screen that contains no information; empty space.

46.6 Software

Form Designer (The Learning Company), Formtool 97 (International Microcomputer Software, Inc.), Informs (Novell), and Jetform Design (Jetform Corporation) are examples of form design software packages. Screen design tools are often incorporated in prototyping and CASE software.

46.7 References

1.  Davis, W. S., Business Systems Analysis and Design, Wadsworth, Belmont, CA, 1994.
2.  Galitz, W. O., Handbook of Screen Format Design, QED Information Systems, Wellesley, MA, 1989.
<ch45 toc ch47>