Notebook Format


Please write as legibly as possible. Keep in mind that others may need to refer to your notes long after you have left the lab, and your notebooks will be useless if they are illegible.

Please organize your notebooks as outlined below. Again, the idea is to make it easier for people to understand your notes after you have left the lab. Attention to lab notes is not optional in this lab -- it is required. Your notes are every bit as important as the experiments you perform.

Write out your plans before you start your experiment. This practice will allow you to anticipate potential problems and will ensure that you have all the reagents and supplies you need before you get stuck in the middle of a protocol. Never undertake a new protocol without checking to be sure all reagents are available in the lab. If they are not, order whatever is needed. Do all necessary calculations ahead of time. This can be critical for embryo or cell culture -- you don't want your precious samples sitting around while you try to figure out what and how much to add. You are also much less likely to make mistakes if you have thought the experiment through beforehand. While all of this may seem self-evident, many people don't bother to plan ahead, and their work shows it.


  1. Start a new page for each separate experiment. The goal is to give some organization to your notes so that they will be easy to follow, even months or years later. Lab notes should not be entered in stream-of-consciousness fashion. The actual determination of what constitutes a separate experiment is somewhat arbitrary and is left to your discretion. For example, the preparation of a radiolabeled probe for a Southern blot could be listed separately (e.g. if a portion will also be used for colony hybridizations) or as part of the Southern blotting experiment write-up.
  2. Notes should be carefully dated. Date each new entry. If you later annotate a write-up to reflect new thoughts or conclusions, date and cross-reference your annotations. This is very important -- it makes clear to anyone reviewing your notes that these additions were intended as annotations, not as fraudulent changes.
  3. Each individual experiment should be given a number. The system you use is up to you but should be consistent. For example, 99-78 might be 1999, experiment 78 (and 78-1 or 78.1 would be page 1 of that experiment). Your initials plus the experiment number would also be acceptable, but the advantage of using the year is that it will make it much easier for you to find things in the future. I strongly encourage using the year (the reason for this will be more apparent after you have read section 5).
  4. Keep a running table of contents; it will be much easier to find things later on.

    Each experiment should also contain the following information:
    Sufficiently descriptive to allow quick recognition of contents AIM (where appropriate)
    What was the rationale for designing the experiment in this way or for choosing this set of conditions?
    As detailed as possible, including calculations, recipes for buffers, or other reagents, etc. If you do something very routinely and have made no changes at all in the protocol, refer back by number to an earlier experiment. If you have changed conditions from an earlier protocol, refer back to that experiment and summarize the changes.
    RAW DATA (where possible)
    Including scintillation counter or spectrophotometer printouts, autorads (dated and indexed with experiment number), etc. If your large autorads are kept in a set of old film boxes, make sure it is clear in your notes where a particular autorad can be found.
    What size fragments lit up on a Southern blot? Did the diagnostic digests you performed on a new plasmid prep match the map? Which of a series of reaction conditions worked most effectively? If you take the trouble to do this routinely, it will save you a great deal of time later on: You won't have to reinvent the wheel constantly.
    Are there any caveats about the interpretation of the results? Might the experiment work better if the conditions are changed slightly the next time? If an experiment did not work or was uninformative, what factors might make a difference? (Unless you are sure you made a careless mistake in designing or executing an experiment, it is not worth repeating the experiment until you have spent some time trying to determine what might have gone wrong.) What is the next step?

  5. NUMBER ALL SAMPLE TUBES WITH AN EXPERIMENT NUMBER BEFORE YOU PUT THEM AWAY. A system of this sort makes it much easier to locate samples and reduces the amount of information you need to include on tube labels. Your samples should also ALWAYS be dated. A tube labeled 1, A, etc. is unacceptable; it is too easy to collect a lot of tubes and then to forget what they contain.
  6. Occasionally, after a long series of similar experiments, it is useful to go back and review the results and then write a summary. This practice can save you an enormous amount of time when you are ready to prepare a manuscript or begin writing your thesis. If appropriate, design a template sheet that can be used to record and summarize data (we have these for embryo cultures; analogous sheets could be designed for embryoid body assays and clonogenic cultures, protocols that you use on a regular basis and prefer not to rewrite in detail each time, etc.)