The two most important home tests to do when trying to assess whether or not it is in your pet's best interest to proceed with euthanasia are the Quality of Life test and the Pain list. 

First, lets look at the Quality of Life Scale:

A scoring system for life quality called the HHHHHMM Scale was developed by Dr. Alice Villalobos. The letters stand for: Hurt, Hunger, Hydration, Hygiene, Happiness, Mobility and More Good Days than Bad.  It is an excellent tool for evaluating and keeping track of your pet’s Quality of Life as the disease or end of life process progresses.  For more information, please visit our Quality of Life page.  In order to perform this test, assign scores from 0-10 on each of the criteria on the scale.  A score of 35 or more indicates acceptable Life Quality. 

Quality of Life Scale: The HHHHHMM Scale
Pet caregivers can use this Quality of Life Scale to determine the success of pawspice care. Score patients using a scale of 1 to 10. As a reference point, a 10 would be given to a pet who is exhibiting the appetite, happiness, mobility, etc... of a 2 year old pet in the prime of his/her life. A score of 1 is extremely poor. The lowest the score, the worse the Quality of Life. A score of 35 or above represents acceptable Life Quality. In order to get as accurate a score as possible, please refer to the text in the Quality of Life Page which gives additional information regarding each of the criteria below.
Adequate pain control, including breathing ability, is of top concern. Trouble breathing outweighs all concerns. Is the pet's pain successfully managed? Can the pet breathe properly? Is oxygen supplementation necessary?
Is the pet eating enough? Does hand feeding help? Does the patient require a feeding tube?
Is the patient dehydrated? For patients not drinking enough, use subcutaneous fluids once or twice daily to supplement fluid intake.
The patient should be brushed and cleaned, particularly after elimination. Avoid pressure sores and keep all wounds clean.
Does the pet express joy and interest? Is the pet responsive to things around him or her (family, toys, etc.)? Is the pet depressed, lonely, anxious, bored or afraid? Can the pet's bed be close to the family activities and not be isolated?
Can the patient get up without assistance? Does the pet need human or mechanical help (e.g., a cart)? Does the pet feel like going for a walk? Is the pet having seizures or stumbling? (Some caregivers feel euthanasia is preferable to amputation, yet an animal who has limited mobility but is still alert and responsive can have a good quality of life as long as caregivers are committed to helping the pet.)
When bad days outnumber good days, quality of life might be compromised. When a healthy human-animal bond is no longer possible, the caregiver must be made aware the end is near. The decision for euthanasia needs to be made if the pet is suffering. If death comes peacefully and painlessly at home, that is okay.
*A total over 35 points represents acceptable life quality

Adapted by Villalobos, A.E., Quality of Life Scale Helps Make Final Call, VPN, 09/2004, for Canine and Feline Geriatric Oncology Honoring the Human-Animal Bond, by Blackwell Publishing, Table 10.1, released 2006.

**For help in assessing the "Hurt" criterion, see the section on "Understanding Pain".

It is recommended to start keeping track of your pet's Quality of Life scale score as soon as you know that he has a terminal disease or as soon as you realize that he has a chronic progressivew condition (such as arthritis).  Keep a journal with his QoL scale score and the date.  You can repeat the test monthly, weekly, daily... depending on how fast his condition is progressing.

I also recommend that you make a sort of a contract with yourself early on.  Sit down and think of your pet's favorite activities, the things he enjoys most, his current condition...  and think of how far into the illness you want to take your pet.  Write down some of the things that are likely to happen as the condition progresses and what you wil not permit to happen (for example, that you will make the decision before the time comes when he cannot get up anymore, or list some of the things your pet likes to do and make a contract with yourself that once he ceases, for example, to be interested in his favorite toy, won't wag his tail at your arrival, doesn't enjoy his walks... etc...  those are just examples.  Make the list personal according to your baby's favorite things.)

Pain indicators

In order to assess if your pet is in pain, you can scan the list below and see if your pet exhibits several of those pain indicators.  For a more precise use of this list, as in the case of seeking to achieve optimal pain management, it is recommended to print the list, date it and place a score from 1-10 on each of those pain indicators (0 being that the symptom is absent and 10 being maximum manifestation of the symptom).  Then repeat the test a periodically after initiating pain management or modifying your pet's pain management protocol.  Keeping track of these symptoms and how their intensity varies throughout the course of the disease will help you monitor the progress and the success of any pain management being conducted. You can compare the scores gotten from week to week by looking at the prior results and put them in date order in a folder.  And it will also enable you to see when pain management is no longer effective and when it may be time to let your pet go.

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1. Droopy head
2. Droopy ears
3. Tucked tail
4. Does not want to play
5. Lack of social interaction
6. Does not enjoy games
7. Subtle lack of alertness gradually increasing to a deep apathy (early sign will be subtle)
8. Diminished appetite
9. Body tension
10. Facial tension
11. Accepting treats or food gingerly (particularly if pet used to accept them enthusiastically)
12. Lack of interest in walks
13. Doesn't respond when called
14. Worried or sad facial expression
15. Ears pulled back or flattened
16. Eyes wide open to expose “white of the eye”
17. Avoidance of direct eye contact
18. Lips may be retracted, exposing the teeth in a submissive grin (dogs)
19. Almond shaped eyes (caused by facial tension)
20. Whiskers pulled back against cheeks (caused by facial tension)
21. Uncomfortable when resting
22. Shifts frequently when resting
23. Head held abnormally low
24. Difficulty getting up
25. Excessive panting (particularly when it is not hot)
26. Shivering/trembling/shaking
27. Unsettled
28. Pacing
29. Difficulty moving after a long rest
30. Difficulty lying down
31. Slow or unusual gait
32. Limping
33. Hunched back
34. Compulsive licking or rubbing of a certain body part
35. Looking at sides or other body part suddenly and/or worriedly
36. Suddenly running away from “nothing in particular”
37. Can't jump on couch or bed
38. Reluctance to lie down
39. Sleeps in a position that avoids a certain body part from touching the ground or bed
40. Any change in normal sleep patterns
41. Purplish tongue color (NOT gums: tongue)
42. ”Guards” a particular body part
43. Reluctance to be touched in a certain area
44. Reluctance to be picked up
45. Lying down at a distance from everybody and somewhat isolated
46. Disinterested in surroundings
47. Unusual attention seeking
48. Flinching when touched in a certain area
49. Doesn't rest easily when lying down
50. Aggressive behavior to protect a particular area
51. Aggressive behavior on a usually docile pet
52. Crying when a particular area is touched
53. Wakes up at night
54. Does not sleep well
55. Refusal to go on walks
56. Moaning
57. Whimpering
58. Refusing to eat
59. Pressing head against wall (if head pain is present)
60. Unable to get up
61. Crying in pain
62. Teeth clenched, biting down on an object (particularly cats)
63. Howling/screaming uncontrollably