It is very important to assure high quality digital recordings to enjoy error-free medical transcription. If the dictation lacks clarity, it can lead the transcriptionist to misinterpret the facts in recordings and result in erroneous documentation. So what makes a quality digital audio recording? It depends on two recording parameters:
Compression Rate – The size of digital recordings in a particular format is reduced to transfer them quickly between recorder and computer or between computers. This is termed compression. There are two types of compression, namely lossless (retains the quality but possess lower compression ratios (WAV)) and lossy (reduces the quality for high compression (MP3, AAC, WMA) compression. Both WAV and MP3 formats are used for digital dictation. However, these are too much for voice-only recordings as human vocal range (about 4,000 to 7,000 kHz frequency) forms a very small portion of entire frequency range. This paved way for the advent of Digital Speech Standard (DSS) format which produces very small files that can be transported easily while preserving fidelity. DSS Pro, the improved version, comes with increased fidelity, in-recorder encryption and additional demographic information. Digital recorders such as the Olympus DS-5000, Olympus DS-5000iD, Philips DPM 9600 and more support this format.
Sampling Rate – Sound files are usually sampled 8, 11, 22 or 44 thousand times a second. Though you can get more exact reproductions with high sampling rate, it is possible to understand the human voice at a lower sampling rate. The commonly used sampling rate for dictation files are 8 kHz (8,000 times per second) and 11 kHz or 16 kHz (DSS Pro). The terms QP (Quality Play), SP (Standard Play), LP (Longer Play) and EP (Extended Play) are used to indicate different sampling rates. The rate applies to each term may differ according to the recorder.
As your dictation requirements may differ based on your purpose, the format and sampling rate will also vary. For example, if you want to transcribe patients’ health information (diagnosis details, laboratory test details and more) from recordings, then you should maintain its confidentiality in accordance with HIPAA law. In such cases, the most suitable format is DSS Pro as it supports in-recorder encryption. Sometimes, you may need longer recording time with slightly less quality (in the doctor and patient encounter). You can choose a lower sampling rate in such cases.
It is always better to consult with experts about the type of format and sampling suitable for your digital dictation so that you can generate quality audio recordings. Some professional medical transcription companies offer a quality digital recorder free of cost for volume transcription orders.